As Kochanski prepares to leave, she says that it may be possible to communicate transdimensionally, via the cellular phone she carries. As they load aboard some supplies from Kochanski's ship, Lister sees a crate with a strange symbol and asks about it. Kryten explains that the symbol, a snake eating its own tail, represents infinity. The symbol is on the crate because it contained everlasting batteries... called Ouroboros batteries, Ouroboros being the name of the symbol. Lister realises that the box he was found in didn't say "our Rob or Ross" but "Ouroboros" and suddenly works out the mystery behind his abandonment. The invitro tube Kochanski has is Lister himself, and at some point after the baby is born he will need to go back in time and leave him at the Aigburth Arms, writing "Ouroboros" on the box so he would be able to work it out at this point in time. Lister begins to try and come to terms with the fact that he is his own father, and Kochanski is not only his ex-girlfriend but also his mother, before realizing he needs to get the tube back from Kochanski.