So... I just had an idea, a small plot bunny: What would Team Flash's worst nightmares be? And it turned into this story that's all about Caitlin/Cisco/Barry fluff! (No slash) Just bromance and a touch of SnowBarry, but also WestAllen. Just know this is my first Flash fic!

Hope you enjoy!

Disclaimer: I unfortunately do not own the characters... those rights belong to the CW.

Beware, there are several mentions of suicidal thoughts! It's pretty dark. If you're easily triggered by such topics, this story probably isn't for you!

"Maybe you just need to breach it to a different earth next time," Caitlin suggested.

"Next time?" Cisco exclaimed, his eyebrows raised in disbelief. "You think we'll get another chance to catch Cicada's lightning-bolt-Mjolnir-weapon-thing?"

Iris shook her head. "No, Barry and Nora can't go back in time again to get what we need. This was our only chance at getting rid of it."

Cisco leaned back in his chair. "Well... Then I guess our best shot at defeating him lies with a certain someone we know," he beamed, looking pointedly at Caitlin.

The latter pressed her lips together and nodded, tapping her fingers against her arm thoughtfully.

There was a sudden gust of air, followed by a flash of fiery yellow, and Barry was suddenly standing in the middle of the room. He spun around, looking around the room in a way which made him appear to be very confused.

"Barry?" Iris said. "What's wrong?"

His wide eyes fell on her, then shifted to look at Caitlin and Cisco. "You- you're here? But..." Barry's voice trembled as he spoke. "No... I saw you..."

He started shaking his head. Caitlin noticed that he was sweating profusely, his hands shaking as he frustratedly pulled them through his hair. She rose from her chair and started moving slowly around the desk towards him. "Bar? Talk to us."

His eyes flickered across her face. "I- I saw you... and Cisco... she killed you - I should've stopped her... if I'd just... but I wasn't fast enough." Barry squeezed his eyes shut as though in pain, breathing rapidly.

"Come on, dude, you're not making any sense," Cisco said, frowning. He, too, moved slowly toward Barry, as though he were an animal that would scare easily. Cisco held his hand out as he approached Barry, reaching for his distressed friend. Caitlin realized what he was trying to do.

"It's okay, let us help you," she coaxed gently. "We're right here."

"No," he moaned, backing away, "no, no. I can't, it's my fault - I won't go on without them, I-" He interrupted himself as tears began falling down his face. "God, what have I done..."

Caitlin threw an anxious glance at Iris at his words. I won't go on. If he thought that they were dead...

"Barry, don't do anything stupid," Iris whispered wide-eyed, voicing Caitlin's concern.

"Iris," he breathed, his eyes filled with longing as he moved towards her. Barry took her hands in his. "I'm sorry... I'm so sorry, but I can't live with this-" His eyes filled with pain again, and he moved away, looking around the room for something.

"Cisco," Caitlin hissed, "you've got to do something. Reach him - the real him!"

Cisco nodded, moving determinately toward Barry, and placed his bandaged hands on his friend's shoulders before the latter could protest. He and Barry both gasped, and went completely still.

xXx

"How is this possible?" Barry said where he sat, leaning against the wall, as he rubbed a hand across his face.

He seemed to have calmed down significantly. Cisco had come out of the Vibe with a nosebleed, but it had worked; he'd managed to explain to Barry what was going on. That what he'd seen couldn't have been real, but they were.

"Must be a meta-human," Iris said, crouching beside her husband, and placed a comforting hand on his shoulder.

"Yeah, like, maybe the one you were chasing when you stopped responding to your ear-com," suggested Cisco sarcastically.

Barry frowned. "I was speeding after a meta-human?"

Caitlin tilted her head. "You don't remember?" she asked.

Barry shook his head, gazing up at her as though he expected her to have all the answers. She bit her lip. "Let me run some tests on you, okay?"

He nodded, and she took his hand to pull him up from the floor and started guiding him toward the medical wing.

"All we knew when we sent you after her was that she was robbing a bank," Cisco explained as they walked, "and when you got there, you said it was as though all the people there were frozen. Now I'm thinking they might've been frozen with fear."

"Isn't being afraid a pretty normal reaction when there's a robbery going on?" Iris intervened. Caitlin let Barry down on the bed and grabbed her stethoscope.

"Well, yes, but normally the robber asks you to get down on the floor so that you're less of a threat, and the workers are asked to get the money under threat..." He paused. "At least, that's what always happens in the movies," Cisco added. "But in this case, they weren't even moving. Barry, you described it as they looked as though they were somewhere far away."

"So, you think they were seeing things, things that made them just as terrified as I was just now," Barry deduced. Caitlin moved on to shine a light in his eyes.

"I think maybe she locked them in their own personal nightmare," Cisco concluded.

"But Barry wasn't locked in place," Iris said questioningly. "He ran all the way back here to see if Cisco and Caitlin were okay."

Cisco shrugged. "People have different reactions to fear. I would assume our hero here doesn't freeze up when he's afraid, while people who aren't usually running around doing the things Barry does on a daily basis, might have a harder time."

"That makes sense," Caitlin agreed as finished taking Barry's blood pressure. "There's nothing physically wrong with him, no drugs or poison that would make him see the things that he saw. I believe it was purely psychological; his brain believed it, which triggered the physical reactions to fear such as shaking, sweating and shortness of breath."

"So, we're looking for a meta that can make you see what scares you the most," Cisco said bitterly. "Sounds fun!"

"Not just what scares you," Barry said, looking down at his hands which he wrung around each other. "The worst possible thing you can imagine, like, the stuff of your darkest nightmares." He looked up at Cisco. "I told you before, when we fought DeVoe; losing both of my best friends, and it being all my fault..." He shook his head as though pushing the memory away. "Her visions are designed to break you."

"And when your brain is occupied with what it's seeing and hearing as though it were real, she's free to do whatever she wants." Caitlin shook her head. "We need to stop her."

"And we will," Cisco said. "She has to be on of the meta's created by the dark matter from the satellite, right?"

Caitlin nodded. "She's definitely not from the particle accelerator or the bus."

"Guys," Barry interrupted, his voice urgent. When they looked over, he was clutching his head, squeezing his eyes shut again. "It's still happening."

Cisco frowned. "I thought I stopped it when I got into his head."

"Seems your Vibes can't override whatever she manipulated inside his head," Caitlin said, moving over to Barry. She grabbed his hands and gently pulled them away from his face, forcing him to look at her. "Barry, we're fine. You need to believe that."

He grimaced. "I hear you saying that, but then I hear you saying that I should know it isn't real - I keep seeing you die!"

"What do we do?" Iris exclaimed, moving to her husband's side.

"I need it to stop," Barry moaned, slamming his fist onto the bed.

"I have an idea," Cisco suddenly said. He rushed out of the room and returned a minute later, holding a pair of power-dampening cuffs. "Let's try these."

Caitlin took Barry's hands once more, allowing Cisco to place the cuffs around his wrists. Barry immediately went still, visibly relaxing. He looked around, blinking as though he was seeing the scene around him for the first time.

"Better?" Cisco asked him.

Barry nodded and gave a small smile of relief. "A lot."

Caitlin smiled back at him. "The only problem is, we now have a meta on the loose and no Flash to fight her," she said.

"But we have XS," Iris suggested. "And Ralph, and Cisco."

"And Killer Frost," Cisco added, winking at Caitlin.

She nodded determinately. "Okay, but before we go, we need to do our research. We can't waltz in there unprepared - she'll lock us in our own nightmares before we can say-"

"Dreamlock!" Cisco grinned, making a celebratory gesture. "Still got it."

xXx

They were all staring at the monitors, trying to take in what they were reading. The meta's name was Annabelle Montassouri. Her brother, mother and father had all perished the night that the satellite exploded. Caitlin knew that was not a coincidence.

"No wonder she needs money," she said in a low voice. "She lost her family as well as her home that night."

"I can't believe we did this to her," Nora mumbled.

Barry suddenly looked stricken. "If she knows that we did this... it's no wonder that she would come after me. And if that's true... I led her straight to all of you at S.T.A.R Labs."

"We're all vulnerable," Iris breathed.

"Well, then we need to figure out how to stop her," Ralph said, "and fast."

Cisco held up his finger. "I have an idea," he said. "Maybe I can build some sort of force field that'll interrupt any outer wavelengths she's trying to send into our brains."

"That's good, Cisco!" Caitlin smiled. "That'll work."

"I'll get right to it." He marched out of the room.

Caitlin sat down in front of the monitors, trying to read up on her. "She must've been dreaming when she was struck by the dark matter from the satellite explosion," she realized. "That's how she got her powers. She's so in tune with the brainwaves of dreams that she's able to manipulate the ones of those around her."

Ralph seemed to think about this for a moment. "Do you think she can give you good dreams too?" They all turned to scowl at him.

"What?" he said, and, with a smirk, "Just imagine what she could do when you're-"

There was a loud crash down the hall. Caitlin looked at Barry with wide eyes. "Maybe it wasn't very smart to leave Cisco alone with a meta that wants revenge on all of us on the loose."

Barry shook his head, and they both rushed down the hall. Turning the corner, they found Cisco sitting on the floor, shards of glass spread around him. He was crying silently, and his knuckles were cut and bleeding.

"Cisco!" Caitlin called out, kneeling carefully beside him, avoiding the pieces of broken glass.

"Caitlin," he croaked, "I'm s-sorry!"

"Cisco, it's okay, it wasn't real-" Barry started.

"Barry," Cisco breathed, "oh, I'm so sorry, I didn't have a choice... I couldn't help... but I'll make sure it never happens again-"

He lifted his hand, revealing a particularly long shard of glass that he had been clutching. He pressed the sharp edge against his wrist...

"NO!" Caitlin reacted instinctively, reaching out to grab the back of the hand that was holding the piece of glass. She pulled it back, and the glass moved away from his wrist, but he was resisting her, resulting in a sort of tug of war to occur between them. Desperately, she took a hold of the shard of glass itself and yanked it out of his hand before throwing it several feet away from them.

"Barry, grab the power dampening cuffs!" she ordered him as she locked both Cisco's wrists between her hands in an attempt to keep him from hurting himself.

"Caitlin, stop," Cisco whispered. "Why are you doing this? I- I don't deserve-"

Barry returned moments later and immediately locked the cuffs in place around Cisco's wrists. The latter blinked, stunned. "Oh, thank god," he mumbled, closing his eyes briefly. "That was terrifying."

Barry squeezed his shoulder. "Whatever happened, it wasn't real, okay?"

"I know, but damn... it felt real."

Barry nodded sympathetically. "I know, buddy."

Caitlin grabbed Cisco's arm to help him stand. "You okay?" she asked him.

"I think so..." he trailed off, looking down. "Are you?"

Caitlin frowned. "What do you mean?"

"Cait," Barry said softly, "you're bleeding." He reached out, gently taking Caitlin's hand in his, revealing the palm of her hand. There was a small gash where the shard of glass she'd pulled out of Cisco's hand must've cut her.

"Oh," she said and brought it closer to her eyes to inspect it, pulling at the edges. "Doesn't need stitches," she concluded.

"Caitlin, I'm so sorry," Cisco began, but Caitlin held up her uninjured hand.

"Cisco, don't, please," she said. "It wasn't your fault, okay? Besides, it doesn't even hurt."

Cisco just shook his head slightly, looking ashamed.

"Any point to keep working on that force field?" Barry asked. The question was aimed at Cisco, but since he still looked a little out of it, Caitlin decided to step in.

"Let's try and track her down to see if she's left already," she suggested. "If she thinks she's got us locked in our nightmares, she could be far away already."

"If she tried to attack the building, why was only I affected?" Cisco asked them.

Caitlin frowned, thinking about it. "She must need to be able to see her victims. That's why she could entrance everybody at the bank, but only take us down one at a time."

"But I've never seen her," protested Cisco.

"She must've been in here when you left to work on the force field," Barry realized. "She couldn't barge in and take us all on at the same time, so she found the perfect opportunity when one of us were isolated."

"Then that's the solution!" Cisco suddenly exclaimed. "That's how we stop her! We need to prevent her from seeing us."

Caitlin smiled; an idea was already forming in her head.

xXx

"I've got a ping on her location!" Cisco called.

"The game is on!" Ralph quoted, pulling down his mask.

"Be careful, alright?" Iris said, pulling Nora into a hug.

"Always, mom," she said with a laugh.

"Caitlin," Barry said, "you and Killer Frost ready?"

I was born ready, Killer Frost's voice echoed in her head, and Caitlin smiled. "Ready."

"Alright, seeing as I can't open a breach right now," Cisco said, "XS, you can run us there, can't you?"

"Uh, sure!" Nora smiled. "Grab on!"

From Caitlin's perspective, the world around her simply blurred, strong wind whipped through her hair, and then it stopped abruptly. She wobbled but managed to stay on her feet, looking around. They were standing in a dark and empty alley. There was a sudden small screech and Nora yelped, "Sorry!" as Ralph patted out the fire on his suit. The stretchy material of his suit appeared to be the least fireproof out of all of their outfits. Caitlin was wearing clothes in Killer Frost's style, durable and easier to move in if it came down to a fight, and Cisco was wearing his suit and glasses. Though he could not use his powers with the cuffs on, they were hoping Annabelle would be stunned to see that he wasn't broken by the induced nightmare.

"She should be right in here," Nora said, gesturing at the building to their left. It looked abandoned, but Caitlin suspected that was not the case.

"Alright, let's do this," Cisco said, rubbing his hands together.

Ralph opened the door and together they snuck inside, trying to stay as quiet as possible. Caitlin held her hands by her sides as she walked through the door, ready to produce an icy blast. She looked around as she entered, and the scene before them was... very odd. The room was edged in moving boxes. Square in the middle of the room stood a lonely bed with chains attached to the headboard.

"This girl is into some freaky shit," whispered Ralph, one eyebrow raised as he took in the room.

"Where is she?" Nora mumbled, turning her head back and forth.

There was a moment of silence as they moved through the room, all senses on high alert.

"Up here," a high voice suddenly called. They all looked up to where the voice came from. She was standing on a loft section of the room, resting her arms on the railing as she looked down at them. Her hair was raven-colored, her skin pale. But it was the blood-shot eyes and angry red burns on her wrists that drew Caitlin's attention.

She gave a cold laugh, and as she did, her eyes turned black. Her head began to glow, like an aura, except the light was an electric lilac.

"Now, Caitlin!"

Let's do this, Killer Frost said inside her mind.

Together they summoned the cold powers, bringing frost to their hands, and they sent it up - not straight into Annabelle, as they weren't trying to kill her. Instead, they let the frost cloud the air around Annabelle like a fog. Ralph started to make himself longer, reaching up to the loft to put power-dampening cuffs on her-

There was a shout and something catapulted out of the loft. It took Caitlin a second to realize that it was Annabelle - she had jumped. Before Caitlin knew it, Annabelle had landed on the bed in a swift somersault. The former along with Killer Frost started creating the frost again, but Annabelle's head was already glowing - a bolt of electric lilac shot toward her and sent her flying. Caitlin rolled across the floor and she stayed down, the wind knocked out of her.

Cisco, Ralph and Nora immediately moved in on her. Nora started running circles around Annabelle, creating a swirl of dust that made it hard for Annabelle to see. Coughing, Ralph threw Nora the power-dampening cuffs. She caught them and moved with super-speed to put them on Annabelle, but she was suddenly struck by the electric lilac energy and she too was sent flying. The cuffs were knocked out of her hands and sent skidding along the floor.

Ralph, standing several feet behind Annabelle, quickly elongated his arms so that he could cover her eyes with his hands while keeping his distance. Annabelle growled and started clawing at his hands, thrashing to get free, but Cisco had seized the opportunity. He dove for the cuffs, tossed them to Nora who once again super-sped toward Annabelle, and this time, managed to get the cuffs locked onto her. The lilac glow immediately faded away and Annabelle stopped struggling, looking stunned as Ralph removed his hands.

"We did it!" Nora exclaimed excitedly, and Ralph gave her a high-five. Cisco on the other hand was looking around the room, his frown deepening by the second.

"Uh, guys?" He said slowly. "Where's Caitlin?"

xXx

Nora had sped them back to S.T.A.R Labs, where they'd realized that the influence Annabelle had exerted over them did not go away until she made it so. This meant bad news for Caitlin, but they had at least gotten Annabelle to remove her hold over Barry and Cisco in exchange for not turning her over to the police. She thought she wouldn't have to spend years in prison at Iron Heights, but of course, little did she know that they were planning to keep her in their holding cells until they were sure she wasn't a threat to anyone anymore.

"How are we going to find her?" Barry said, pacing back and forth in the cortex. "If she's trapped in her nightmare... I mean, we saw what Cisco- he almost hurt himself-"

"Don't go there, okay?" Iris said soothingly. "She'll be okay."

"Maybe we can track her by Killer Frost's cold signature, just like we have before," Cisco said, starting to type on the keyboard.

"Bar, we'll find her," Iris reassured him. He nodded, but didn't seem any calmer. Then he suddenly stopped abruptly, his eyes wide. "That's it," he said.

"That's... what's what?" Cisco said confusedly.

"Killer Frost!" Barry repeated. "If she has any influence at all right now, she'd probably try to send us a message..." He disappeared in a flash of yellow lightning, and reappeared just as quickly, holding something in his hand.

He laughed breathlessly, holding up a post-it note. "'NOT a suicide note. The bridge. Hurry. -KF'," he read aloud.

Cisco rounded the table, closed his fist and opened up a breach. "You heard the girl," he said, "let's hurry."

Barry nodded, and the two of them stepped through the breach together.

xXx

Caitlin, don't do this! Killer Frost tried to convince her. Remember, this isn't real. You want to live!

"I know," she cried, throwing one leg over the railing, "I know you hate me. I thought this was what you wanted."

No, Caity, you're not hearing me right.

She groaned. "No, I hear you. One second you say you need me, only to tell me you wouldn't miss me the next." She pulled her other leg up and stood on the edge of the railing, looking down at the water far beneath her. The scientist part of her immediately calculated that she wouldn't survive the fall.

Iris, Ralph, Cisco, Killer frost said, Barry. You know they would all miss you. They need you, they always will.

Caitlin shook her head. "You heard them as well as I did. They never forgave me for trusting Harrison Wells, or Jay-"

They never said that. Caity, Barry wasn't even at Annabelle's lair!

"Y-yes he was, he was... outside, waiting for us. He hates me," she sobbed. "And Cisco, he hates me too, and Iris never liked me, I-" She hiccuped. "I'm all alone."

No, you're not. I'm right here!

"- and you'll be here, ready to take over when I die, I know, you've said it about t-ten times," Caitlin whispered, and braced herself, leaning over the edge. Nobody loved her anymore. She wasn't even sure if she could love again. So what was she really worth? All the knowledge and education she had... it didn't matter if the people close to her despised her. No, it was about time that she ended it.

Caitlin, don't do this! Killer Frost begged her. Please!

"I'm sorry," she breathed, tears falling silently down her cheek. "You'll finally get what you wanted."

And she jumped.

Or, rather, she would've jumped, if her feet weren't stuck to the railing. She looked down and saw that her feet were enclosed in ice, edging all the way up her legs.

I won't let you do this, Killer Frost growled, I won't let you kill us both!

"Don't w-worry," Caitlin said, "you won't have to k-kill me yourself." She bent down, gritted her teeth, and broke off a piece of ice, sharp as an icicle.

Oh, for God's sake, Killer Frost swore, where the hell are they?

Caitlin moved the icicle toward's her chest, held it above her heart-

"Caitlin!"

She turned to look behind her. Cisco and Barry seemed to have appeared out of nowhere. Her heart dropped. Had they come to spew out some more insults? To tell her how worthless she was, how much they hated her? She felt she'd heard it all.

Before she could even make a move, a streak of fiery yellow passed her by, and the icicle was suddenly gone. Barry stopped a few feet away, throwing the icicle onto the ground. "Cait, don't do this," he said in a low voice.

Did he really mean that? Caitlin pressed her palms to her forehead, grimacing. She couldn't tell what was real. Was she going insane?

Cisco was moving toward her. "Caitlin, I can help you," he promised. "I can show you what's real. Just let me help."

Her heart was thumping hard in her chest. "Why would you want to help me?" she cried. "You hate me."

Cisco frowned. "Why would we hate you?"

"You've been nothing but kind to me since I woke up from the coma," Barry said softly. "We've been through so much since then. I could never hate you."

"Neither could I," Cisco added, smiling at her, tears in his eyes. "I told you before, Caitlin, all the best moments of my life have been with you. You're my best friend.

Caitlin shook her head, her lip trembling. She felt like she couldn't breathe. She was shivering and sweating at the same time.

"Cait." Barry held out his hand. "We love you."

The words echoed in her head. We loved you. Now we need you out of our lives.

And we won't even miss you, Cisco's voice echoed in her mind.

The pain in her heart went so deep that she felt like her heart literally shattered. In the blink of an eye, she broke off another icicle and stabbed it into her chest.

"NO!" Barry and Cisco yelled, moving forward, fear written plainly across their faces.

But for Caitlin it was only a short moment of pain, because Killer Frost finally managed to break through. They didn't shared the same mind - Killer Frost hadn't hallucinated what Caitlin had - but their body and the physical pain she shared, and it fueled her. Survival instinct drove her into control. She froze Caitlin's movements, stopping the icicle before it reached their heart, and yanked it out. The tip was coated in blood, and she threw it away, pressing a hand to the bleeding wound.

The moment of surprise was apparently wearing off, for Caitlin started fighting her for control again. Killer Frost felt herself weakening rapidly.

"Hurry!" Killer Frost shouted as her legs buckled. "I can't hold her for much longer."

Barry sped toward her. Killer Frost used the last of her strength to remove the ice that held Caitlin in place, and disappeared into unconsciousness. Caitlin wobbled on the railing, tilting backward toward the edge-

Barry grabbed her. Of course he did. When it matters, he is always in time, was Caitlin's last thought before the pain in her chest overwhelmed her and she passed out.

A/N: Please leave a review telling me what you thought! Do you want more chapters?

Thank you lovelies!