Cold in the Heads — Gerald Hammond

Dry wit and nautical lore run through this mystery Lady P is a scientist, inventor and engineer ? but above all she's a fun-loving and youthful grandmother. But she doesn?t see the funny side when the dead body of a youngish woman turns up on board her daughter's sailing boat. Even Inspector Plummer cannot prevent Lady P's natural inquisitiveness landing her in deep water ? and in hospital. But gradually clues surface with very unpleasant ramifications for all concerned.