Red Dwarf: The Movie is a film version of the long running British television series called Red Dwarf. Made to celebrate it's 30th anniversary it shows Dave Lister, Arnold Rimmer, Kryten and Cat going on a journey through time and space, causing them to experience what has happened, what is happening, what could have happened and what will happen. The film also has cameo appearances of nearly every character to appear in Red Dwarf.
On Earth, a young Arnold Rimmer complains about the planet, as his older brother Howard bullies him. Running off, he bumps into a young Dave Lister. While both contrast each other in everyway, they quickly earn each others respect when Lister fights off Howard and when Rimmer pushes Lister to safety, avoiding a speeding car. Before parting ways, they shake hands, but forget to tell each other who they were.
Billions of years later, the present Rimmer is complaining about how Lister plays the guitar. Before the argument can continue however, Cat tells them of a "mean, green squiggly thing". It is soon revealed to be a tear in space-time by Kryten, before it sucks them in.
They crash land and find, to their shock, themselves to be on the nova 5 and encounter the original Kryten. Present Kryten, despite trying to figure out what is happening, is constantly distracted by how his past self reacts, resulting in him deactivating his past self.