Blackthorn House is a 1949 detective novel by John Rhode, the pen name of the British writer Cecil Street.

[1][2] It is the forty eighth in his long-running series of novels featuring Lancelot Priestley, a Golden Age armchair detective.

[3] A man finds that the car he has recently bought is stolen property.

Even more alarmingly there is a corpse with a body concealed in it, that links to the country mansion Blackthorn House.

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