Weirdo doc likes to conduct experiments in the basement of his house at his wealthy wife's expense. She hates his guts because he allowed their son to die. This is one reason he spends most of his time drinking and popping tranqulizers. His friend warns him about side effects, including hallucinations. We assume that the skull's antics are merely in his mind. Never for a moment would we believe that the skull really is able to perform these feats...
I won't give the entire story away, but what follows involves a skull that is burned in a fireplace to the fascinating sound of wah-wah disco guitar, thrown out the front door late at night during a storm, and all the while continually reappearing and tormenting and eventually killing everyone! Chomping and whistling and causing havoc. One guy tries to reason with the skull. He dies moments afterward. The eerie harpsichord music adds to the flavor of the early-1970's made-for-TV feel of this warped wonder. What I saw was a black and white kinescope, though my guess is that this was originally aired in color?