The House on Haunted Hill is the ninth episode of the popular 1969 ITC British television series Randall and Hopkirk (Deceased) starring Mike Pratt, Kenneth Cope and Annette Andre. The episode was first broadcast on 16 November 1969 on ITV, and was directed by Ray Austin.

Jeff is hired simultaneously on two apparently separate cases, one investigating a diamond theft from the company Mortland, the other investigating a haunted house, Merston Manor, for an estate agent, Mr. Webster. Realising he can't work on both cases at once, Jeff compiles witness statements from workers at Mortland, while the ghost Marty is sent to investigate the manor. Jeff in his spare time visits the manor and is scared away by ghostly phenomenon upstairs.

Jeff is summoned alone to a warehouse meeting, whereby he is threatened by the Mortland company sales director, Walter Previss, and offered £5000 if he writes the case off as an outside job. Rejecting both bribe and threat, Jeff goes ahead with his plan to expose Previss and is only halted when Previss reveals they've kidnapped Jeannie's sister to ensure his silence.

Searching for Jenny, Jeff is contacted by Webster asking why his car which he'd lent to Jenny - was parked outside his house. Realising the manor is where the kidnappers took Jenny he travels there to investigate. With Marty too terrified to find out the strange phenomenon upstairs, Jeff investigates and discovers a sensor in the wall that triggers an electronic ghost system upstairs to scare away visitors and that the house is being used as a hideout for the diamond operation. Jeff goes upstairs but is overpowered and tied up along with Jenny, and it's left to Marty to get help. He attends a psychic meeting nearby where the manor is being discussed, and contacts an elderly speaker to communicate with the rest of the group. Together, they descend on the manor, rescuing Jeff at the last minute, though thanks in part to Previss, who decides to free Jeff and Jenny rather than murder them as instructed.

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