When several men are found dead in New Jersey with the same strange looking bite marks on their bodies, Skinner orders Mulder to investigate. Mulder discovers a genetically mutated creature that is stalking its victims in Newark's underground sewer system.

Puck reappears in this episode as he calls the group to invite them to a party. None of the cast members show up but a few days later, while at a bar with Judd, a drunken Rachel calls Puck to invite him down there for some drinks. After fighting as usual, Rachel storms off and vows never talk to Puck again. This vow is then broken soon after as he calls to try and repair the damage. The two meet in a park only to fight, yet again, about the cast's reasoning for kicking him out of the house. This dispute initiates the search for a new roommate and after interviewing three individuals, the group decides on Jo, a young woman from London. Jo's friend Steve takes Cory and Rachel rock climbing soon after she moves in, which helps break the ice between the cast members and Jo.

Fueled on by his desire to seek vengeance against the immortal mutant that changed him into a weapon of evil, Archangel persaudes Rogue into helping him hunt down and destroy Apocalypse.

Tensions run high in Holby as foot-ball fans gather for the Saturday match. For Kevin, a rookie policeman, the simple arrest of a drunk biker has tragic consequences. Meanwhile, a disabled young girl poses a challenge for new nurse Jude.