The story is set in Galloway, a part of Scotland popular with artists because of its landscapes. Sandy Campbell is a talented painter, but also a notoriously quarrelsome drunkard. When he is found dead in a stream, with a half-finished painting on the bank above, it is assumed at first that he fell in accidentally, fracturing his skull. Lord Peter Wimsey, who is in the region on a fishing holiday, points out the inconsistency which makes it impossible for Campbell himself to have worked on the painting. Campbell's death is now a murder case, and Lord Peter investigates!
