Adam, Bree, and Chase are looking for Leo because he is late for training and find out he is in Mission Creek because Janelle threatened to break up with him. S-1 shows up unexpectedly and shocks everyone. She came to the island because, like everyone else, her memory is blank, but has continuing flashbacks of Krane. No one believes her until she suggests taking out her chip. Chase and Douglas realize that she has a doomsday virus in her because she was under the influence of the Triton App. Feeling it is worse than he thought, Chase uses his scan ability and finds out that the students, Adam, Bree, and himself also have the doomsday virus implanted in them. Bree accidentally blurts out that they are all going to die and everyone starts to panic. Chase and Douglas try to find a way to save everyone before they die. Leo comes out of the hydro-loop and attacks S-1, unaware that she does not have any memories of their encounter, knocking her unconscious. Elsewhere, Adam and Bree are disappointed when they find out time is running out on them and they decide to have one last hurrah before they die. Adam wants to break the world record for blowing the most balloons with his pressurized lung capacity ability, while Bree wants to have a party with all of her friends from Mission Creek. S-1 wakes up, and Leo knocks her out again out of fear. Adam does a webcast, in which he shows everyone he's breaking the record for blowing the most balloons, but Bree walks in and is upset because instead of saying, "You're all dear to me, so I'm having a party," on an invite, she mistakenly writes, "You're all dead to me, so I'm having a party." S-1 comes to again and relives the memory of Krane giving her the encryption code to try to destroy the virus, with Douglas playing Krane and Chase playing S-1, to no avail. When Adam finds out how upset Bree was because she could not get her friends to come, Adam invites random strangers from the pier. Bree still wants her friends to come, but she is glad to know she has a brother who cares. Douglas and Chase are unable to find a way to stop the virus until Chase plans to have everyone temporarily die so he can give themselves doomsday viruses. Chase does not have time for Douglas' backup plan, so he relies on Leo to finish the job. Chase starts to explain what Leo should do, until everyone dies. Douglas returns to synchronize his laptop's firewall to the virus, but he instead follows Chase's plan and saves everyone. Everyone is virus-free, and Leo and S-1 decide to let bygones be bygones.