Friend of the Devil?

 

 (imdb)

THE DEVIL'S PARTNER-1960-An old man is killed when sacrificing a goat in a supernatural ritual. Then Nick Richards (Ed Nelson) comes to a small town looking for his uncle Pete. He's informed by the sheriff (Spencer Carlisle) that his uncle is dead and it could be murder. Local girl Nell (Jean Allison) befriends him. Her boyfriend David (Richard Crane) owns a gas station and her father (Edgar Buchanan) is the town doctor. Later Frank, another local drinks goat's milk and dies. Nick seems nice but he obviously has a sinister ulterior motive. At night Nick, using a pentagram his uncle made, makes David's dog turn on him. He survives by killing the dog and hires Nick to run the station while he recovers. Later Nick kills the plastic surgeon who's coming to check out David's scars by making his car crash. For some reason Nick pays the town drunk Papers (Byron Foulger) to help him in another ritual where Nick transforms into his uncle Pete! Papers runs away and is trampled by a mysterious black horse. Later Nick turns into a snake and tries to kill David but is shot. He turns into the black horse but is shot and killed by the Sheriff. The horse turns into Nick who turns into Uncle Pete. 

There seems to be a few holes in this story or the version I saw was edited. This is only one of two feature length films made by busy TV director Charles Rondeau and both in 1960 (the other was the dreary THE GIRL IN LOVER'S LANE). The screenplay was co-written by ex-Bowery Boys actor Stanley Clements.

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