The Final Sin (1977)

"Daddy", a rich and sex crazy guy trapped in a wheelchair because he returns paraplegic from war and grows bitter. He can only satisfy his thirst by forcing other people bizarre sex games. His sex hungry wife, Marrianne, his precocious daughter, Mona and his sensitive adopted son, Phil helps - just pawns in his lovemaking. The paid couple Linda and her muscular lover, Buster provide 'Dad' every fantasy when they visit family. "Dad" is watching on closed circuit television because curly Linda explores his juicy wife in the bathroom. His admiration turns to ecstasy as they move from climax to climax using sex toys "Daddy" provided. Nymphet daughter and shy son give 'Pope', a few surprises, and Buster is used in a way that he normally would never obey. Evening explodes change that stuns everyone. One day "Daddy" decides to play a bizarre psycho-sexual game with his wife, daughter and adopted son.