Wallace (Peter Sallis), a mild-mannered Englishman with a penchant for Rube Goldberg style inventions (and cheese) finds he must take in a lodger to make ends meet. A penguin answers his ad, and slowly but surely pushes out Wallace's loyal (and intelligent) dog Gromit. When Wallace is implicated in a series of robberies, will Gromit be able to clear his name?
