Cyril is the only squirrel in Lake Park, and he's very lonely. Until one day he meets Pat - Pat the big, grey . . . other squirrel. Cyril and Pat have lots of adventures and fun together and Cyril is so pleased he's made a friend. But everyone says that Cyril and Pat simply cannot be friends, and they soon reveal why: Pat, as the reader has known all along, is actually a Rat!

But Cyril's life turns out to be a lot duller and quite a bit scarier without Pat by his side, and in the end the two friends learn that some things are more important than being the same, or listening to others.