The Man With Two Brains (1983)

A world famous brain surgeon (Steve Martin) marries a duplicitous gold digger (Kathleen Turner) who taunts him by withholding sex from him while she has sex with the gardener and room service waiters. But when he comes across a brain (Sissy Spacek) in a jar in a scientist's (David Warner) laboratory, it's love! Directed by Carl Reiner, who co-wrote the screenplay along with Martin and George Gipe. This parody of science fiction "mad scientist" movies is quite funny. It's totally silly of course so don't look for logic or realism, just enjoy the jokes. Kathleen Turner is hilarious as the evil, ball busting vixen in what might be described as her BODY HEAT character  for laughs. Spacek proves that voice acting can be just as important as "real" acting as her brain is a charmer and you can see why Martin would fall in love with her/it. All in all, one of the funniest comedies of the 1980s. The underscore is by Joel Goldsmith (son of Jerry). With James Cromwell, George Furth, Estelle Reiner, Randi Brooks, Jeffrey Combs and Merv Griffin.