It's 'veggie-mania' in Wallace and Gromit's neighborhood. The two enterprising friends are cashing in with their humane pest-control outfit, "Anti-Pesto." With only days to go before the annual Giant Vegetable Competition they find that their business is booming. They come to find out that running a "humane" pest control outfit can have its drawbacks. Suddenly, a large and mysterious veg-ravaging "beast" begins attacking the town's sacred vegetable plots at night. The competition hostess, Lady Tottington, commissions Anti-Pesto to catch the beast and save the day. But Victor Quartermaine would rather shoot the beast and secure the position of local hero - not to mention Lady Tottingon's hand in marriage.

Three pets set out across a wilderness to find their family and the children they love and miss.