Animated series about a young guinea pig and her little brother, who look to solve police investigations. The sovereign of London animals is concerned by a series of cat abductions in the Marylebone neighbourhood. One cat who managed to escape speaks of a sort of giant ant that spurts liquid on cats to immobilise them before carrying them off.

Goliath the dog, the terror of the park who is feared by all homeless animals, finds an adversary stronger than himself: a creature with a black coat and luminescent eyes that stands on its hind legs like a werewolf.