Flushed Away (David Bowers & Sam Fell, 2006)
In the opening minutes of Flushed Away, the rat Roddy (voiced by Hugh Jackman), who spends a life of leisure as a solitary house pet, gets flushed down the toilet. He enters the sewers of London where he finds a whole society of rats: initially horrified, he wants nothing more than to escape from the proletarian rats (proletarirats?) and to reach the surface. But with the help of the attractive Rita (voiced by Kate Winslet) he comes to savour the company of his fellow rats.
