“Can of Worms” is the sixth and final episode of Red Dwarf XI.
The Dwarfers are leaving a medistation in Starbug, and Kryten has salvaged a personality altering machine and, surprisingly, Rimmer volunteers to have some personality surgery. When Kryten explains what this involves, Rimmer bolts. Not so surprisingly.
Starbug then goes off course, because Lister fell asleep. Because he overdid it at lunch. They are well of course and a long way from Red Dwarf, and a suggestion is made to cross through some Gelf country. Or rather asteroid belt. They are vampire Gelfs and feed on the blood of virgins. Cat gets worried. Unfortunately for him, he qualifies. Not that he is willing to admit it. Lister says he doesn’t want to open up the titular can of worms regarding the subject.
On the way back, the long way round, they receive a distress call from a transport ship carry a mercenoid and a prisoner. The transport ship is about to pass the event horizon of a super massive black hole. Rimmer says they have no reason to risk their lives. He stays behind as the others go aboard the ship in a scene rather reminiscent of a scene from Aliens. Until Rimmer makes it all go silly, as he hadn’t read the manual.
The mercenoid proves to be less of a threat than might be thought. Which probably means the prisoner is going to be a serious problem. Although the prisoner turns out to be a female cat. Cat is really excited by this. So we get both of them going ‘that’s mine’ about everything, something that hasn’t been seen in quite a while. However, she’s not a feline sapiens, but in fact a Polymorph. Rescuing it was a bit of a mistake then. Especially as it’s sort of pregnant, and is looking for a host for its eggs. Which does not bode well for Cat. So, they have to save the Cat, but there’s a problem.