A message pod reaches Red Dwarf from Diva-Droid International, manufacturers of Kryten (Robert Llewellyn) and the 4000 series of mechanoids. It announces that Kryten's built-in expiry date is almost up and his in-built shut-down chip will automatically activate in twenty-four hours time. Kryten resigns himself to his fate, telling Lister (Craig Charles) he's going to his reward in "Silicon Heaven". Lister tries to tell him there's no such place, to no avail. Lister is determined Kryten's going to enjoy his last day in a profitless and non-practical way. He even goes to the trouble of building the robotic Marilyn Monroe kit that's been hanging around the ship for years, whilst Holly (Hattie Hayridge) knocks up a special android home brew using Vimto and liquid nitrogen.
Waking the next morning with a hangover, Kryten realises that he had experienced true pleasure for the first time and decides that he'd much rather delay his departure. He can override his shutdown programme, but the catch is that his replacement mechanoid comes fitted with instructions to kill its predecessor if necessary. But Lister, Rimmer (Chris Barrie) and Cat (Danny John-Jules) won't let him onboard. They're going to stand by their shipmate.
The replacement mechanoid, Hudzen's ship lands on the landing gantry, and the crew prepare for his appearance. Lister tells Hudzen that Kryten is staying put and that he should leave. Hudzen refuses to go away and advances down the corridor proving to be dangerously insane as he tries to kill everyone. Just as Hudzen is finally upon Kryten and about to deliver a killing blow, he is told the lie that silicon heaven doesn't exist. Hudzen's mind can't cope with this revelation and shuts down.