The episode opens with Lister in an uncharacteristically depressed mood; he tells Cat and Rimmer that he hates his life on Red Dwarf. During the conversation, Rimmer reminisces about a former schoolmate, Thickie Holden, who despite being one of the stupidest boys in class went on to earn an immense fortune with an invention called the "tension sheet". Meanwhile, while working in the ship's darkroom, Kryten discovers that a mutated batch of developing fluid produces photographs that are windows to the past, and slide projections that one can step into (albeit only within the confines of the photo). After a quick trip to Frank Rimmer's wedding and to an Adolf Hitler speech, Lister goes back in time and changes history by giving Thickie Holden's invention to his 17-year-old self. This creates unforseen changes in the present; Cat and Kryten disappear, leaving Arnold Rimmer alone with Holly. Rimmer visits Lister, hoping to persuade him to come back to Red Dwarf; Lister, however – now living in a mansion with a supermodel – fails to recognise him, and tells the butler to throw him out. Rimmer then decides to go still further back in time to give the idea for the tension sheet to his childhood self first. Rimmer's plan is foiled when Thickie Holden overhears Rimmer's conversation with his younger self, and takes the invention for himself. Upon returning to the present, everything is put back exactly the way it was - with the sole exception that Rimmer is now alive, not a hologram. Delighted, he rushes out into a corridor and accidentally blows himself up.