Happy Mother's Day, especially to any moms who teach physics.

"What do you mean you won't do it?"

Oliver gave Curtis his best intimidating stare as the two of them stood eye-to-eye in the lair. It had worked well in the past, but this time it appeared to be having no effect. Curtis simply stared back at him as Digg looked on in mild amusement.

"I'm sorry, Oliver," Curtis said firmly. "You know I'd help you if I could – I love being part of Team Arrow. This time, though, I'm really not the man for the job."

Oliver did his best to hold his temper. What he needed seemed simple enough, well within Curtis's abilities. Apparently, Curtis thought differently. Oliver took a moment to collect himself. As tempted as he was by the idea of grabbing their new resident geek and strangling him, he knew that was not going to help. He took a deep breath. "Well, if you're not the man, who is?" he asked as patiently as he could.

Curtis shrugged. "Felicity."

"Felicity's the man for the job?"

"The job involves inserting a bunch of executables onto HIVE's servers to help us track the location of key operatives as well as gather information on their next moves. So, yes - Felicity's exactly the man for the job."

"You can't do the same thing? I thought you had her skills and then some." If intimidation wouldn't work, maybe a challenge would.

It didn't. Curtis frowned thoughtfully and said, "I could try. But doing the job right also involves hiding the executables so that HIVE's IT guys don't find them, trace them back to us, or delete them. Stealth is Felicity's forte, not mine. Once she gets access to the servers, she can do this job in 15 minutes. It would take me a couple of hours at least – and even then I wouldn't be sure if I'd done it right. You really need to ask her."

Oliver sighed. He'd seen Felicity numerous times in the months since they'd broken up, but other than the few minutes after Laurel's funeral, he hadn't spent any meaningful time alone with her. That day had been awful, yet somehow it had felt right sitting with her in the limo - and almost a little too good. It had felt like the old days, when Felicity had held an unquestioning belief in his ability to save things - an unquestioning belief in him. Sitting with her in the backseat he had felt the gulf between them narrow, if only for a moment and only just a tiny bit. It was progress, but it wasn't nearly enough for him to be asking her favors, especially joining him alone on a mission.

He shook his head. "Felicity's not an option. You have to do this one, Curtis." He made it a statement and not a request.

But Curtis held his ground. Damn, the man could be stubborn. "No, Oliver. If you want to get this done safely, quickly and right you need Felicity." Studying Oliver's face he added, "Look, if it's asking her that has you worried, I can ask. Once she understands the situation, I'm sure she'll do it. She wants to take out Laurel's killer as much as any of us."

Oliver wasn't nearly as certain. The situation involved traveling 20 miles outside of Star City to a HIVE datacenter to implant malware on servers that would then send information back to the lair. They were hoping to track Darhk's movement patterns with the goal of finding him when he was least well defended. After an evening of trying to break into the servers from the lair, Curtis had determined that the job could not be done remotely – it required physical access. Fortunately, the datacenter was not heavily guarded. HIVE seemed to assume that the remote location and nondescript appearance of the building gave it a decent amount of protection. After 6 pm the place was just about deserted, with only one or two guards on duty. If Felicity really could do the job in 15 minutes, then it appeared to be a no-brainer. But it would mean an hour or two together in close proximity, without the buffer of Curtis or John. And it carried vague reminders of an earlier time, when Oliver and Felicity had broken into the Merlyn mainframe.

Oliver studied Curtis's tenacious expression. "Fine," he said at last, "Ask Felicity. Assuming she says yes, we'll go tomorrow evening."

Curtis just about beamed. "No problem. I'll stop by her place on my way home to talk to her, and give you a call right after I do." He headed almost jauntily for the elevator, and the lair was left to Oliver and Diggle.

"Did that seem a little strange to you?" Oliver asked Digg. "Usually Curtis is begging to help out."

Diggle shrugged. "Maybe." After a moment he added, "What's really worrying you, Oliver? That Felicity'll say no or that she'll say yes?"

Oliver wasn't sure he was in the mood for Diggle's insights. "What exactly does that mean, John?"

"It's been a while since you've spent time alone with Felicity. With Laurel's death and everything else that's been going on, you've pushed the breakup to the back of your mind and you're in denial about how much it's hurting you. You do this datacenter job tomorrow and you'll be forced to consider how much you really miss her."

Oliver thought about it. "It sounds like if we do this right, it'll be quick - a couple of hours, tops, and we'll be pretty busy. Hardly time to delve into our feelings." At least he hoped so.

Diggle nodded. "Right."

Predictably, Felicity agreed to do the job. She showed up at the lair after work the next day, dressed in black, stretchy jeans, low heeled ankle boots, and a black hoodie. If she felt any unease at working with Oliver, she didn't show it. She stood next to him as Curtis walked them both through the schematics of the HIVE datacenter and they picked their best options for ingress and egress. She asked Curtis a few questions about HIVE's IT security procedures in a measured, matter-of-fact voice. She was all business. To Oliver, the message was clear. She was pro, he was a pro – they'd done this before and they could do it now without any pesky emotions getting in the way. Fine – he was all onboard with that.

The first snag came with transportation.

Oliver had assumed he would suit up and they would take the bike. It was the preferred mode for all Arrow missions – fast and nimble if they needed a quick getaway, and frankly much cooler than a car. Laurel and Speedy always preferred the Ducati.

It wasn't until they were getting ready to leave that it dawned on him that having Felicity on the bike would mean having Felicity pressed up against his back, with her arms around his waist. Not exactly the same thing as toting your sister. Felicity had never ridden the bike much in the old days. Her short dresses and tendency to be in the lair rather than in the field made it an infrequent event. The few times she had ridden with him, however, had been quite stimulating for both of them – and usually the prelude to even better activity afterward. He watched the color drain from her face as she remembered exactly the same thing. They both turned toward Curtis.

"Curtis," Oliver said crisply, "Can we borrow your car?"

Curtis looked puzzled. "My car? Aren't you going to just take the bike?"

Oliver cleared his throat. "The weather doesn't look great. Chance of rain tonight."

Curtis shook his head. "No…no…I checked a few minutes ago," he said confidently. "Dry as a bone." When Oliver continued to stare at him he added more determinedly, "Look, I don't think it's a good idea to have The Arrow using my car. If you're caught on video somewhere, it's going to be hard to explain."

Felicity chimed in, clearly in Oliver's corner on this one. "You can just say it was stolen, Curtis."

Curtis shook his head. "Nah…to make that work I'd have to report it stolen to the police. And if I report it stolen, then they'll be looking for it while you're still out there breaking into datacenters…well, you get the idea. I don't think that's gonna work."

Oliver turned to look at Felicity. She shrugged slightly and once again assumed a business-like expression. Clearly she was back to I'm a pro, you're a pro. Well, if she could do it, so could he.

"Alright," he agreed reluctantly. "We'll take the bike."

Fortunately, planting the software in the datacenter went as smoothly as Curtis had predicted. Oliver and Felicity broke in undetected, found the server exactly where they expected it to be, and got Felicity's software installed and running in less than 15 minutes. Oliver breathed a sigh of relief as they headed toward the door and Curtis and John, listening on the comms, congratulated them on a job well done. As Oliver and Felicity climbed onto the bike, Curtis announced that he and Digg were signing off for the night and would talk to them in the morning.

The second snag came as they were about to ride away from HIVE's datacenter.

Apparently they hadn't gone as undetected as they'd thought, because a couple of shots rang out and the dust on the ground next to them kicked up as Oliver started the bike. Looking over his shoulder, Oliver saw a single guard coming toward them with his pistol raised. The guard fired again and Oliver felt Felicity flinch behind him. Oh Christ, he thought, not a second time. Oh please, not a second time.

He could barely get the words out. "Felicity, are you hit?"

She squeezed his waist. "No, Oliver," she said reassuringly, "I'm not. It's just the sound – any time I hear a gun now I think about…" her voice trailed off.

Thank God. Oliver found he could breathe again and hit the throttle for all he was worth. The Ducati's tires squealed as they sped away. After a few minutes he asked Felicity, "Is anyone following us?"

She glanced over her shoulder. "I don't see anyone."

"Well, let's not linger." He kept the bike at a steady 80 miles per hour as they raced along the winding road back toward Star City. Even during the day this was a little used route; at close to 10 pm, it was deserted. He tried a couple of times to raise Curtis and Digg on the comms, but the two must have really meant it when they said they were headed home because he was met with silence. It didn't seem too important. No one was tailing them and, at this rate, they'd be back to Star City in 15 minutes.

The third snag came when the Ducati began to sputter.

Oliver ignored the first cough from the bike's engine. He'd been riding the Ducati over four years now as The Arrow and the thing had never failed him, despite rough terrain and some hairy skids. Oliver had almost come to think of the bike as a friend, another loyal and tough member of the team. Felicity had tuned it up regularly – she possessed freakish automotive skills along with being an expert hacker - and it had always run like a champ. It occurred to him now that she hadn't looked at the bike since they'd broken up and, like all things mechanical, it was not infallible. He made a mental note to add motorcycle maintenance to Curtis's list of duties. Too late to be of much help tonight.

He pushed on the throttle and with one last, desperate gasp, the Ducati died.

He and Felicity got off and he pushed the bike over to the side of the road. "What do you think?" he asked her. "Can you fix it?"

She raised an eyebrow and gave him her best sardonic look. "Normally I'd say yes, but given that I don't have any tools and it's close to pitch black, I'm going to go with a resounding no. Remind me to dock Curtis's pay when we get back for not lending us his car." At least she was still trying for a little humor.

Oliver reached under his hood to remove his mask. It seemed pretty safe under the circumstances, and he wanted any future conversation with Felicity to be as Oliver, not The Arrow. "Well, my best guess is that we're still about 10 miles outside of Star City," he said. "Given that you're wearing sensible shoes," – he resisted adding for a change – "we can be there in less than three hours if we walk."

"Fine by me."

He nodded. "I'd suggest we move off the road and into the woods, just in case someone did follow us. It's only a quarter moon, but there should be enough light for us to keep the road in sight."

"Right. Let's go."

The first time Felicity stumbled, Oliver didn't think much of it. It was dark, after all, and they were walking on uneven ground. The second time really didn't register either. But the third time she tripped – when she nearly fell on her face – he moved behind her and began to pay attention. And once he started watching, he couldn't help but see that her legs were moving awkwardly, as if she weren't in full command of them. Something clearly wasn't right.

"Felicity?"

She didn't turn to look at him and kept moving clumsily forward. "Yes, Oliver?"

"What's wrong with your legs?"

"Nothing's wrong, Oliver. I'm fine."

Bullshit.

"Felicity," he tried to keep his voice gentle, to not make it an order, "Please talk to me."

She stopped then, but didn't turn to face him. Instead, she said in a strained voice that he could barely hear, "I think the power's dying."

"The power?"

"To my chip - the chip in my spine. My legs aren't doing what I want them to do because my chip is running out of energy." She sounded embarrassed, as if it were somehow her fault.

He didn't know what to say. Once she had gotten out of the wheelchair and started walking again, he hadn't thought much about the miraculous technology that had made it possible. The chip, her determination, her optimism - they had all become bound together in the wondrous being that was Felicity Smoak. That a silly mechanical malfunction like a low battery could bring her back to paralysis had never occurred to him. Yet it was an uncertainty that she had to live with every day, that she was living with right now. Even with the chip, things were never going to be exactly the same for her. He was ashamed that that thought had never occurred to him, that he had assumed the chip had allowed life to go back to exactly what it had been before she'd been shot.

Stupidly, he said, "I thought the chip ran on the Palmer super-battery thing. You know, the battery that never runs out of energy?"

She sighed. "The chip does run on it. But what makes the Palmer-Tech battery special is its ability to recharge itself. When energy output isn't needed, there's a unique electro-chemical reaction that restores power. With my chip, the battery normally recharges while I'm sitting in my office or while I'm sleeping. But today I've been on my feet pretty much since 6:00 in the morning. Curtis had me doing walk-through's of a number of labs all day, I had a brief presentation to the Board, and then you and I went to the datacenter. I don't think I've sat down once. I guess we're identifying the limits of the battery. I realize it's a lousy time to be finding them out." There was a tremble in her voice as well as a note of apology. She sounded like she was hitting her limit.

Oliver felt something fall inside him, as if his heart had dropped from his chest to his gut. He'd spent the whole day thinking about how difficult the datacenter job was going to be for him – without recognizing that it was equally as difficult for her. And now, to top it all off, her chip was out of power and she was physically failing. Talk about a lousy day. He thought briefly about picking her up and carrying her, but knew he couldn't do that for 10 miles. He glanced around the woods. They were a decent distance from the bike and it was unlikely any of Darhk's Ghosts were going to find them in the blackness. He felt relatively safe.

"Okay," he said to Felicity. "Why don't we stop here and rest for awhile? I don't think they can find us. How long will it take for the battery to recharge?"

She pondered that one. "Four hours, maybe? I'm not sure."

"Well, let's sit for a couple and then we can test it."

Even in the dark, the relief on her face was evident. "Thanks, Oliver."

They moved another twenty yards or so away from the road, then stopped when they found a small cluster of pine trees. There was a blanket of soft, brown needles on the forest floor, dry and fragrant. If it were noon and summer, Oliver thought, this would be a pleasant place for a picnic. As it was, they could certainly do worse. He leaned his back against a tree and watched Felicity settle hers against another nearby. And for the first time that evening, Oliver felt really alone with her – no Curtis on the comms, no distraction of the mission. Just him and Felicity, sitting together in the dark. She closed her eyes.

Silence descended.

He thought she had fallen asleep, until he noticed her body trembling. He was wondering if it was nerves or maybe pain, when he realized that it had gotten pretty chilly. He didn't mind too much – he had a thermal shirt on under his leathers – but Felicity was basically wearing a cotton hoodie over… well, who knew what she was wearing under it? His mind travelled briefly to a favorite black, lacy bra she sometimes wore under dark outfits – his favorite bra, mind you, not hers. The memory alone brought additional warmth to his body. Her trembling, on the other hand, grew stronger.

"Felicity?"

"Yes?" Her voice was shaking as well as her body.

"Are you cold?"

"A little," she admitted. "I probably should have dressed more warmly, but it was still daylight when I left my place and I felt really comfortable. I wasn't thinking about how cold it might get when we lost the thermal radiation."

"The thermal radiation?"

"Yeah…you know, from the sun?" she explained. When he said nothing, she added, "It's one of the three forms of heat transfer: Radiation, convection, conduction."

He almost laughed. Trust Felicity to turn being stranded and cold in the woods into a treatise on the physics of heat transfer. He was about to call her on it when it dawned on him that she might be trying to make him laugh, perhaps to ease the awkward situation or to avoid talking about anything personal. After all, he used physical activity to hide; she used science and humor. He decided to go with it.

"So, explain radiation." he said conversationally. "As you know, I never passed any of my physics classes."

She responded immediately, with a smile in her voice. "Radiation is when heat is exchanged at a distance, without any physical contact. You know, like when you step from the shade to the sun to feel its warmth, or you hold your hand near a light bulb but don't touch it. If the other object is warmer, you feel the heat transfer immediately. When I left my apartment this afternoon it was still sunny…there was plenty of heat radiating from the sun. Not so much now."

She sounded cheerful and a little less shaky. So far so good. Oliver decided to maintain the scientific discourse. "And convection?"

"Convection is when a fluid moving over a body helps transfer heat to or away from it. It's why our convection oven in the loft cooked food faster - it circulated hot air around the food."

Oliver liked her use of "our oven." Every now and then she would do that – slip into a mode of speech that made them sound as if they still shared something, as if they were still together. It gave him hope. He didn't think she was aware that she did it. "So," he continued, anxious to keep her talking, "That's interesting, but I guess convection isn't really relevant at this moment."

"Actually," she said a little more soberly, "It's entirely relevant. Convection can transfer heat to a body, like the oven, but it can also transfer heat away. Think of a wind chill. The cold air blowing over your body carries heat away faster than if there were no wind. Kind of like the way the breeze is cooling us down now."

She was right. The air did seem more gusty than it had a few minutes ago. With his eyes well-adjusted to the dark, he could see her gather her knees and pull them to her chest. She clearly was cold – past the point of it being a discomfort and into the territory of it being a danger. Her shivering had resumed in full force and her cheer from a few moments ago had disappeared entirely. He tried to distract her. "And what about conduction? We haven't covered that one yet."

There was a long pause while she studied her hands. Apparently, conduction was her least favorite mode of heat transfer. At last she said, "Conduction is when heat moves between two bodies that are… in contact. Heat flows from the warmer body to the cooler one. Like when you touch the burner on the stove by mistake, or wrap a hot towel around your body." Her voice was almost despondent when she mentioned the towel. She must be freezing. Oliver glanced briefly at his watch. They had been sitting for about 30 minutes and there were at least another 90 to go before it was even worth testing the power in her chip. Ninety minutes, and getting colder.

He pondered what she'd said about conduction. Two bodies in contact…heat flows from the warmer one to the cooler one…

The wind picked up and she shivered violently. He might even have heard her teeth chatter. That settled it.

"Felicity?"

"Hmmm?"

"I'm pretty sure my body is warmer than yours."

"I'm not surprised," she said matter-of-factly. "Your body always did run warm – you never minded when I pulled all the covers over to my side. The leather is probably helping with the wind chill, too. It's less porous than cotton."

All true, but not the point. He was going to have to try again. He took a deep breath. "What you said about conduction, Felicity? That heat flows from a warmer body to a cooler one through contact? Well, I'm telling you that my body is warmer than yours."

"I heard you before, Oliver. I'm happy that you're warm. I'm not. So what?"

He sighed. He was going to have to spell it out. "So, I'm suggesting that we take advantage of the situation to try a little conduction. Use contact to move heat from a warmer body to a cooler one."

His suggestion was met with silence, and then a gasp. If it hadn't been so dark, he would have sworn that he'd seen the light bulb go on over her head. She put her face in her hands.

"Oliver," she said at last, "I'm not so sure that's a good…"

"Are you cold?" he interrupted impatiently.

"Yes. But I don't think I'm in danger of losing my…"

"Do you think it will help?" he continued briskly.

"Maybe a little. But you and I and…body contact …I don't…"

"Felicity!" he snapped in exasperation. Damn, the woman could be stubborn. "You're freezing and you're shivering. I can hear your teeth chattering over here. For all we know, that's using up energy that could be recharging the battery. If we want to get back to Star City, you need to be able to walk, which means we need to restore power to the chip. I think we owe it to ourselves to give this a go and I'm not going to ask you again. Get your ass over here and let's…try some conduction, dammit."

She exhaled loudly, "Fine." After a minute spent girding her loins – metaphorically - she got stiffly to her feet and stumbled the few yards over to his tree, sinking to the ground next to him. He reached out and pulled her to his side, then half onto his chest. He nearly jumped when she tucked her face into his neck and her freezing nose came into contact with his skin. After a minute, she slid one hand under his leather jacket and tucked it in the waistband of his pants at the hip. They sat – well, half sat, half laid down – once again in silence.

It might have been his imagination, but after a few minutes her shivering seemed to have lessened, although it didn't disappear entirely.

"Better?" he asked.

She nodded, not moving her face from his neck. "Better."

"Good."

The wind picked up further. Even he was feeling it now, despite being huddled next to Felicity and his more effective clothing. Now that they'd gotten over this first hurdle, he wondered if there were anything else they could do to stay warm. He thought about her mini-lesson on heat transfer. "Felicity," he began carefully.

"Yes?"

"Now that we've got conduction, is there anything we can do to cut down on the convective heat loss? You know, reduce the wind chill?"

She thought about it for a moment. "Really, the only thing you can do to reduce convective heat loss is to cut down on the surface area exposed to the fluid. For us that would mean finding a position where less of our bodies are exposed to the air. So, I suppose if we were to try to curl up in a tighter position…"

"What if you lay completely on top of me or…better yet, me on top of you? You'd have your back on the pine needles and me covering your front. Not a lot of surface area exposed to the wind. In fact, the only thing exposed would be my back. Shouldn't that help?"

He cringed almost as soon as he'd said it. Suggesting he lay on top of Felicity to keep her warm was right up there with some of her best verbal gaffs. He closed his eyes, expecting her to either pull away or give him a tongue-lashing.

To his surprise, she did neither. After a long moment, she said softly, "Oh hell. In for a penny, in for a pound." She sighed. "I'm still cold. Let's try it."

Oliver couldn't believe his ears. Before she could change her mind, he gently steered Felicity onto her back on the pine needles, then gradually rested his body over hers, carrying some of his weight on his elbows. The position immediately brought to mind a number of touching, post-coital moments in their history – for her as well as him, he suspected. It also gave him the opportunity to peer down the front of her hoodie and observe that – yes - she was indeed wearing his favorite black bra. To his utter embarrassment he felt himself begin to harden, like a fourteen year old boy with absolutely no control. He was pretty sure she could feel it too. He ducked his head, hoping the hood covered most of his face. He really did not want to meet her eyes.

Felicity came to the rescue. "Oliver," she said slowly, "if it makes you feel any better, I want you too."

It was the last thing he expected her to say and the best thing he could have possibly heard. He blinked hard, and then he did look into her eyes, at the honesty and vulnerability in them. "You do?"

She nodded. "I always want you, and you know I still love you, but it doesn't change anything. I don't think I can be in a relationship where my partner's first inclination is to solve all his problems without me."

"What if I told you that I don't want that either? That I want to change?"

"I'd say – go change, then."

"And if I succeed?"

She smiled. "I'm not going anywhere, Oliver. You know where to find me. But the change has to be real."

Suddenly Oliver felt warm – there was a heat inside him that had nothing to do with conduction, convection or radiation. And if the chip took four hours to recharge – well, that didn't seem like such a bad thing either.

Down in the lair, John Diggle glanced at the clock.

"It's been three hours," he said to Curtis. "How long are you planning on leaving them out there?"

Curtis shrugged. "I'm not sure. Do you think three hours is enough?"

Digg shook his head. "They're both really stubborn people. I'd suggest another hour or two. It's chilly but not freezing. There shouldn't be much risk of hypothermia."

"Right." Curtis went back to typing something into the server.

"You know," Diggle continued conversationally, "I don't think I want to be you when Oliver finds out that you drained most of the gas out of the bike and rigged the gage. Felicity either, for that matter. I assume you've experienced her loud voice? And, technically, she's your boss. She could make your life very unpleasant."

Curtis stopped typing. "I'm hoping for a good enough outcome tonight that both of them forget to be angry," he said softly.

Diggle thought about that one. "Maybe," he agreed skeptically. "But on the other hand, if they end up walking all the way back to Star City, they could be more pissed off than ever."

Curtis nodded. "I suppose so. I did my best to run Felicity ragged today so that the battery in her chip would drain, but I may have underestimated its ability to hold a charge. If all went according to plan, they should be snuggled up somewhere at this moment with nothing to do but talk."

"We could always turn the comms back on and listen in."

Curtis grimaced. "I don't think so. If for some reason things are going really well, I don't want to hear my boss getting down with her boyfriend. I'd never see her the same way again."

Digg shrugged. "I can understand that. Guess we'll find out later then."

"Yup."