What Cisco feared happened: Barry returned to S.T.A.R. Labs that evening with a frostbite injury, a self-loathing look, and bad news.
Even after Caitlin tended to Barry's injuries, they didn't heal as quickly as usual. Barry, unable to bear the pain, groaned, "It's still numb."
Caitlin explained, "It's presenting itself like a third-degree frostbite."
Felicity, who had previously been told that Barry's injuries healed extremely quickly, questioned, "I thought he had hyper-healing."
Caitlin further explained, "It's been slowed. If Barry's cells weren't regenerating at the rate they are, his blood vessels would have frozen solid. The nerve damage would have been permanent. He's lucky to be alive."
Barry, angry at himself for not being able to save the security guard who died in front of him, said, "The person who killed that security guard was Leonard Snart. He's a world-class thief; he isn't even a metahuman. He just had some kind of gun. It froze things. It slowed me down enough that I wasn't able to save someone."
Felicity, upon hearing Leonard Snart's name, immediately looked through the police database and found information about his studies and qualifications. "According to his records, Snart didn't even bother to finish high school. So how did he build a handheld, high-tech snow machine?"
Harrison Wells, who had been silently listening, spoke up, "S.T.A.R. Labs built the cold gun."
Seeing Dr. Wells being open and honest about it, Cisco thought Wells was taking the blame for manufacturing the cold gun, so he hastily added, "Dr. Wells and Caitlin had nothing to do with this. All blame and responsibility lie on me. I built the gun."
Before anyone could speak, Swayam interjected, "No, Cisco. You're not solely to blame. I'm also at fault here. If I hadn't requested your help, I don't think you would have manufactured it."
Barry looked towards them and asked, "You did? Why?"
Cisco started explaining, "Because Swayam required something that could help further improve his physique and make him invulnerable to cold and heat conditions. After you got superspeed, I also realized it could be used to stop you in case you went rogue. Speed and cold are opposites. Temperature is measured by how quickly the atoms of something are oscillating. The faster they are, the hotter it is. When things are cold, they are slower on the atomic level. When there's no movement, it's called..." Before Cisco could continue, Barry finished his sentence, "Absolute Zero."
Seeing that Barry understood, Cisco confirmed, "Yeah. I designed a compact cryo-engine to achieve Absolute Zero. Although it stopped working on Sam since his body adapted to it, it can still affect you and your speed. I built it for Sam for his training, but I didn't dismantle it because I thought it could come in handy. I didn't build it to hurt or harm anyone."
Seeing Barry getting irritated and growing angrier with Cisco, Caitlin spoke before Barry could say anything, "We built the entire structure you're standing in to do good, and it blew up. In the wake of that, you can understand why Cisco would want to be prepared for the worst."
Barry, still angry at himself for not being able to save the security guard, said irritably to Cisco, "I can understand your reasoning, but what I can't understand is why you didn't tell me what you did. I mean, after all we have been through, I thought you trusted me. I thought we were friends."
Seeing Barry's emotional outburst, Cisco walked slowly towards him and said, "We are, Barry."
Before Cisco could continue, Barry said, "If you had just told me, I could've been prepared. But instead, someone died tonight."
Cisco, whose invention was used to take someone's life, was also suffering internally. When Barry mentioned that someone died, he said, "And I have to live with that."
Barry, somewhat calmed down, looked towards Cisco and saw how much it was affecting him. He said, "No, Cisco, we all do." After saying this, Barry left S.T.A.R. Labs.
Swayam, remembering that there was a similar episode in *The Flash* series, initially thought that it was supposed to happen. But when he saw how someone's death affected the team's emotions, he saw them in a new light. He reminded himself that this was his new reality, where innocents suffer the most. From that moment, he decided that if he could save an innocent from a dangerous situation, he would do it.