Stuart Little is back for more action-packed adventure. This time around Stuart and the reluctant Snowbell embark on a dangerous mission to rescue Stuart's new friend Margalo from a villainous falcon. But the journey proves more difficult than he ever imagines, and Stuart has to decide if he's up to the task.

Roddy is a decidedly upper-crust "society mouse" who lives the life of a pampered pet in a posh Kensington flat. When a sewer rat named Sid comes out of the sink, he desides he had hit the jackpot. Roddy schemes to rid himself of Sid by luring him into the "whirlpool." Sid may be an ignorant slob, but he's no fool, but it is Roddy who winds up being flushed away into the bustling sewer world of Ratropolis. There Roddy meets Rita, an enterprising scavenger...