The apparently motiveless murder of two young women points to a psychotic killer. Morse's speculations on what they might have in common leads him to a local garage owner, Jeremy Boynton, who knew them both, and who arouses his suspicions and dislike. Convinced that Boynton holds the key to the crime, Morse begins to hound him, despite having no firm evidence. Morse is also faced with the possible loss of his beloved red Mk II Jaguar.