Donovan's Brain

Lew Ayres plays Dr. Patrick Cory, a scientist who revives the brain of deceased millionaire W.H. Donovan after an experimental procedure in a tank of liquid. As the brain's powers grow, it begins to possess people and Cory struggles to maintain his own free will, leading to a series of terrifying events. Gene Evans plays Dr. Frank Schratt, Cory's friend and assistant who becomes increasingly concerned about the consequences of their actions.