Much different compared to the film, Roderick St. James lives in an apartment, in Kensington, with his owners, until they go away for a holiday. Gilbert and Sulivan, who weren't seen in the film, all help Roddy out with his obstacle course and fencing skills. As they explore more, they hear an explosion, coming from the kitchen. They found that Sid has raided the kitchen and is planning to stay. Roddy schemes to get rid of Sid, but quickly backfires as Sid flushes him down the toilet, thinking of it as a trap. As soon as Roddy ends up in another world, Ratropolis, he bumps into Socketset, who gives him his first task: Collect a jar of flies.