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When Julian had told Barry that they were going to have to identify bodies that had been pulled from the body of water surrounding a boat that had crashed into a pier, Barry wasn't overly fond of the idea. It was cold outside this time of year, which meant that the water had to be freezing. Still, he owed it to these people's families to get an id on their bodies.
"I'm going to go further downstream, see what I can find." Barry tells Julian.
"Okay, just be careful." Julian ordered as Barry walked as far as he could. If he could get further down, then he might be able to save someone. When he got to the edge of the pier, Barry's foot slipped, sending him tumbling head first into the water.
When Barry tumbled into the water, the cold water sends a shock to his entire body. Barry registers a figure in the water. Someone else was in the water, and he needed to save them. Despite his better judgement, Barry swims lower in the water, grasping the figure's arms as he started swimming with them.
Barry's lungs were on fire as he continued to swim, gripping the person's arm as he fought against the waves. Soon enough, he sank again, and that's when he let go of the figure's arm.
Barry was freezing now. He was freezing, and so, so tired. His lungs were burning. They wanted air, and they couldn't get any air. Barry's chest began to feel heavy. Every part of his body was heavy. He continued to struggle against the water. He couldn't give up, not now, damn it!
Barry couldn't fight anymore. He had to breathe, and he had to breathe now. Barry opened his mouth, and he breathed the water in. Barry had stopped struggling now. He slowly closed his eyes, allowing the gentle waves to take him as he finally allowed himself to sink.
Julian was identifying the bodies when he realized that he hadn't seen Barry in a while. Concerned for his partner's safety, he went down to the edge of the pier to see that he was nowhere to be found.
Barry was sinking now. Slowly, slowly sinking. What was the point in fighting, when he had already run out of breath ages ago? Barry hoped that Julian would rescue him sooner, rather than later.
Barry thought of Iris first. They had just started their lives together, and now she was going to lose him. He thought of Joe next. He had two sons now, but now he was going to lose one. He thought of everyone at Star Labs. When he didn't come in the next day, they would know that he was dead. He thought of the city next. They would fall apart when they found out that The Flash was dead. He thought of Julian. He would have died on his watch. He thought of the precinct. They would miss him, they all would. Finally, he thought of Gideon. Without him she would cease to exist, and essentially, so would the wave rider, and everyone on the wave rider. Barry stopped thinking as he finally allowed himself to give up. He stopped fighting.
When Julian couldn't find Barry, he immediately realized that he must have fallen in the water. Without a second thought, he was removing his jacket and his shoes as he dove in after his partner. When Julian finally laid eyes on Barry, he couldn't believe how far down he was in the water. Still, he didn't have time to think about that as he swam down, grabbing his partner by his arms as he pulled them both to the surface.
When Julian surfaced, the sight of Barry almost caused him to stop breathing himself. Barry's skin was blue, which meant that he had been without oxygen for God knows how long. Still, he had to try to get him breathing, as hopeless as it is.
Within seconds he started chest compressions, and rescue breathing. Barry Allen was not dying here, not if he had any say in it. He continued trying to force Barry's heart to start beating, finding that he just couldn't get his heart beating. Eventually he was too tired to continue, and that's when he collapsed, too exhausted, and out of breath to continue.
"Damn it Barry. I told you to be careful. You weren't supposed to die today Allen. What am I supposed to tell everyone, huh?" Julian was sobbing at this point. Damn it, what am I supposed to do? He panics, and that's when he runs away from Barry's corpse.
Barry slowly opened his eyes to find himself trapped in a room. All he could do was watch. Watch the living world, and the dead world. Barry was in neither of those places. Barry had shouted, begged, pleaded for someone to let him out of this place, to let him go to the world of the dead, but it seems that no one was here to grant his wish. Barry felt something warm grab his arm, and that's when he was finally released from this place.
Barry slowly opened his eyes to find himself inside a medical bay. Upon closer inspection, he realized that this wasn't Star Labs.
"Welcome back to the land of the living Mr. Allen!" Rip exclaimed. The first thing Barry felt was his heart beating in his chest. He had been dead for a long time, but now he was alive, only he can't feel his emotions. Shouldn't he be feeling emotions by now?
"Where am I?" Barry asks with confusion.
"You're on the wave rider." Sara answers.
"I don't understand. I was dead." Barry comments.
"That would be me. I found your corpse and brought you onto the wave rider Scarlet. Speaking of which, who said that you could die on me?" Snart informs. If Barry could feel his emotions, he supposed that he would have been shocked upon finding out that Snart carried his corpse to the wave rider, but ever since he was resurrected, he just felt numb.
"Oh. Well, thank you for that." Barry tells him.