Time had stopped for Ivy. She stood frozen to the spot as the love of her life crumpled to the floor, blood blossoming across her chest. An animal scream ripped its way out of her throat, and suddenly it was as if someone had flipped a switch – she leapt across the floor, cradling Eve in her arms, rocking her gently. She could hear someone murmuring something, the same words over and over again, but she was too far outside herself to recognise the sound of her own desperate voice interspersed with tearful gasps.

"No, Evelyn, no-no-no-no. You can't leave me! Don't leave me, he can't take you away from me again…Evelyn, please…please don't leave me, please…no-no-no…" She went on, holding Eve's prone body close to her chest, staining her own skin with scarlet. She buried her face in the beautiful chocolate-brown curls, tangled and limp after Eve's ordeal but still smelling faintly of her shampoo.

Mortimer was also fused to the spot, his terrified stare alternating between the gun in his hand and the desperate tableau on the floor across the room. Before he could think to move, Batman was there, quickly and quietly disarming him and throwing the gun away. He twisted Mortimer's arm behind his back, making him cry out in pain, and leaned down from his considerable height to growl into his ear.

"If you run," he said in a voice that felt to Mortimer as if it reverberated all the way down his spine, "I will break you." With a grunt, the Batman released his grip and threw Mortimer to the ground, slamming the petrified scientist against one of the benches, where he lay shaking with fear. He crossed the room in barely five strides, his cape billowing behind him, and was faced with a Poison Ivy that he had never seen before, in all his years of fighting her. Prostrate and weeping, cradling her lover's limp body in her arms, her shoulders shaking as she murmured the same pleas over and over. He crouched down slowly, as if approaching a wary animal, and spoke in a much softer tone. "Ivy," he ventured.

Nothing. Ivy didn't respond in any way – it was as if something fundamental had stopped working, and what was happening now was a glitch in the system, like a frozen computer screen. She was only dimly aware of any noise around her, and she barely registered Batman's voice when he said her name again, until he changed tack.

"Pamela."

With a jerk, Ivy's head snapped up.

Bruce almost recoiled at the raw pain he saw in her eyes. He could tell, through the tears silently streaming down her face, that something was different. Ivy's not home right now, he thought, and he was right. What he was seeing now were the remains of one Pamela Lillian Isley, presumed deceased; remains that had wilted away, overshadowed by Poison Ivy's darkness, only to be slowly nurtured back to life by the sunlight of real love. Pamela was alive and well, utterly human, and at that moment, completely broken. Bruce knew he would now have to treat her like any other civilian in the middle of a tragedy, rather than the villain he had thought he knew. Very slowly, he reached out his hand and placed it gently on the trembling woman's shoulder. She didn't flinch.

"Pamela, listen to me. You need to let her go." His voice was still calm – between Eve's life hanging in the balance and her own already questionable sanity, he knew that Ivy was barely holding it together.

She shook her head vehemently. "No, no. I can't leave her. I said I wouldn't leave her."

"I'm sure you did," came the reply. "She's not gone yet, Pamela, but if you want to save her, you're going to have to let her go. I'll look after her, I promise." He waited, counting the passing seconds, hoping the message got through that the longer she hesitated, the less time Eve would have.

After blinking several times, Ivy nodded, and released her grip on Eve's body. Bruce rolled her over, then carefully pulled down her pyjama top and pressed a bandage over the wound. Keeping pressure on it, he lifted her up as if she weighed nothing, cradling her in his arms like a bride over the threshold. Ivy, watching from down on her knees, felt a lump in her throat and forced herself to swallow it down. Eve already looked so pale and lifeless, but her chest was moving up and down, and Ivy knew that if she took hold of her wrist there would be a faint pulse under the skin.

Batman cleared his throat, the stern visage back in place. "I can't leave you alone with him," he said gruffly, nodding towards Mortimer, who was looking bleary-eyed and scared stiff. He had managed to push himself off the floor and slump against the bench.

Ivy got to her feet. "I won't kill him. You have my word." Her voice was shaking, but not from trepidation – she was trying to be strong.

Almost before she'd finished speaking, Batman shook his head. "That's not enough."

"It'll have to be," Ivy hissed suddenly, glaring at him. "Don't you dare risk my Evelyn over a moral dilemma! I promise you, I won't kill him. I'll turn him over to the police. Now get her. To. A hospital."

Finally, he nodded. Rather than taking the door, he returned to the window and held Eve close before rappelling down the building and out of sight.

In his absence, the tension in the lab was palpable. Ivy took a moment to gather her thoughts and put her cold, disinterested mask back in place, before walking across the room and standing over Mortimer's cowering form. She looked down her nose at him for a second, the epitome of scorn, before her face broke out into a smile that was more worrying than anything else she could have done.

Mortimer knew: he had fucked up.

"What I said to the Bat? I meant it," Ivy began, still smiling. Her vines, thankful that the worst was over and Eve was now in good hands, revealed themselves once more, slithering around her arms and chest. "I'm not going to kill you. Not because I don't want to – believe me, I really do – but because my Evelyn wouldn't want that. She's funny that way. No, you, Phillip, are going to prison." She crouched down, perfectly poised on her toes. There was no outward sign of the turmoil wrestling inside her body; she knew she needed to be strong, for Evelyn, and make sure that this ended in the way she would have wanted. Eve was many things, but she was not a killer. She would never wish death on anyone.

Not like Ivy would.

"You're going to prison for a very long time," she continued. "And while you're there, and the years tick by, and your life wastes away, you will remember everything you did to her. Everything you did to me. And you will wonder how Poison Ivy, scourge of Gotham City, could possibly be a better person than you." She waved her hand in an almost lazy gesture, and a single vine bridged the gap between them to encircle Mortimer's neck. It didn't squeeze, but sat there, the threat lingering. "I will haunt you, Phillip. I will always be in your head, reminding you of how you stooped below my level, and how you lost everything as a result. Now, get up. You're keeping everyone waiting." She gestured to the window, where flashes of red and blue could be seen from the police cars parked below.

At that moment, the door of the lab flew open, and a team of cops entered, the Commissioner at its head. He didn't look surprised to see what was happening – she supposed Batman had briefed him on the situation. He lowered his gun and approached her with caution, not breaking eye contact.

"Release him, Ivy," he ordered, but still with some trepidation. "He's not your problem anymore."

What did surprise him was that Ivy obeyed almost instantly, calling the vine back to her and letting it wrap itself up in her hair. From there, Mortimer was hauled to his feet and placed in handcuffs, which he submitted to with meek acceptance. Ivy's words were echoing in his mind – he really had lost everything now. To have come so close, to actually meet and speak to her, only to have it all torn away at the last second by his own hand…he hung his head in shame as he was frogmarched from the room and down the stairs. Commissioner Gordon followed, with Ivy walking in step beside him, which was a new experience for them both.

Just as they reached the door of the GCSI building, Ivy put her hand on Gordon's arm and made him stop. When he turned to face her, she met his gaze seriously. "I wanted to tell you something," she said, her green eyes still bright with tears. Through her grip on his arm, Gordon could feel how tenuous the hold on her composure was; her hand was shaking, and the fingers were digging in a little too tight. Patiently, he freed himself and shoved his hands in his pockets.

"Go on, then," he replied. He was honestly a bit freaked out by the bizarre situation, but was hiding it well behind a gruff voice and a big moustache.

"I wanted to say…well, thank you, first of all," Ivy said in earnest. "Thank you for helping me. I know I've never done anything to deserve that."

Gordon acknowledged this with a nod, but didn't say anything. He could tell she wasn't finished.

"Also, you won't have to worry about me being around Gotham anymore. I'm leaving. Or at least planning to. Things have…changed slightly." She stared straight ahead, concentrating on not crying in front of him.

This, Batman hadn't told him, and it came as a shock. "Why are you telling me? Not that I don't appreciate it, but I figured you'd want to keep something like that secret."

Ivy sighed. "Normally, yes, but I've decided to tell a select few. That way, I'm one less thing for you to worry about. If I simply vanished without a trace, you'd always be wondering what had happened to me, if I was going to come back, and when." She reached up and pinched the bridge of her nose, taking a second to collect her thoughts. "I suppose, what I'm trying to say is…I wanted to do you a small favour. Call it a parting gift."

Gordon raised his eyebrows. "Well, thank you, Ivy. I guess I can accept that sort of gift from you."

Finally, Ivy turned her head and looked at him. "You're dying to arrest me right now, aren't you?"

"God, yes." They both chuckled. "But, given the circumstances, and what you've just told me, I think I could see fit to let you off. You did help us catch a kidnapper." The Commissioner was taking a calculated risk here: Poison Ivy was leaving Gotham, and she seemed willing to bring an end to all the trouble she'd been causing them across the years. He could take this unexpected good fortune, or look the gift horse in the mouth and arrest her right there. That, would, however, mean getting in between her and Dr Carter, and given the amount of damage she'd already caused to the city in her grief-stricken state he didn't want to see what else she was capable of when kept apart from this woman she'd apparently grown close to. Much to his chagrin, he was going to let her go.

Ivy was watching him carefully. "So…are we even?"

"Not even close," said Gordon abruptly, "but we can draw a line under the whole thing."

"I appreciate that, Commissioner," Ivy said. Suddenly, Gordon got a proper look at her face in the weak sunlight, and he found himself feeling a little sorry for her for the first time in his life. She looked so vulnerable, so far away from the cold, composed, calculated creature he'd had run-ins with before. He sighed.

"Do you want a ride to the hospital?" he found himself asking.

Ivy stared at him in shock. "I…yes. It would be quicker. Thank you."

Gordon didn't say anything, instead simply fishing in his pocket for his car keys then leading the way out into the daylight.