Mona and Tamsin meet at the moorlands in the Yorkshire countryside. Despite many differences between them, they become true friends. Seductive Tamsin has an upper-class background and is better educated than Mona - the owner of a motorcycle without an engine, who nevertheless is smart and funny. There is also Phil, Mona's brother, who has recently become a born-again religious fanatic. The lives of the three start to tangle and complicate.