D.C.S. Walker goes on leave back to Glasgow, where he is taking care of his increasingly senile mother, he soon becomes involved in the case of a missing woman, who is the sister of an old friend. Walker begins to delve into the life of her then husband Kevin Reid, and discovers a dark bond between him and his brother Ronnie. Soon a body is discovered and is it is proved to be the missing woman. Then Kevin's second wife is reported missing - convincing Walker that one or both of the Reid brothers are involved in the crimes.

Whilst Anna's diary entries initially suggest that Ronnie was stalking her, they are eventually dismissed as forgeries. Ronnie also had an alibi for the time that Margaret went missing and it looks as if he is being framed, possibly by his brother, with whom there is an explosive showdown at a race course.