Villain(s)  Mad scientist, brain in jar

Actor(s):  Lew Ayres, Gene Evans, Nancy Davis, Steve Brodie

Brief Description  Donovan's Brain (1953) is an independently produced American black-and-white science fiction horror film distributed by United Artists. Directed and co-written by Felix E. Feist, the movie stars Lew Ayres and future First Lady Nancy Davis (credited under her maiden name). The film is the most famous adaptation of the 1942 classic sci-fi novel of the same name by Curt Siodmak. It presents a foundational "brain in a jar" storyline, detailing a well-intentioned scientist who becomes telepathically enslaved by the disembodied mind of a ruthless billionaire.

Plot:
Dr. Patrick Cory (Lew Ayres) conducts unorthodox medical research on keeping mammalian brains alive independently of their bodies. He is assisted by his reluctant wife, Janice (Nancy Davis), and a cynical colleague, Dr. Frank Schratt (Gene Evans). A private plane crashes near Dr. Cory's desert laboratory home. The lone survivor is W.H. Donovan, a multi-millionaire industrialist known for being ruthless, cruel, and abusive. Donovan is severely injured and dies under Cory's care. Cory surgically removes Donovan's brain without legal authorization, placing it into an electrically charged, nutrient-filled glass tank to extend its biological life. The brain survives and begins growing in power, pulsating visually when active. It communicates with Cory via telepathy, slowly rewriting his personality.

Dr. Cory experiences a complete Jekyll-and-Hyde transformation. Donovan's mind completely suppresses Cory's awareness, forcing him to limp like Donovan and mimic his handwriting to continue managing the dead tycoon's financial empire, bypass taxes, and manipulate stocks. Dr. Cory becomes an arrogant puppet tasked with clearing obstacles and getting rid of Donovan's enemies. Recognizing his possession, Janice and Dr. Schratt attempt to intervene. Schratt tries to shoot the tank but is telepathically forced by the brain to kill himself instead. Ultimately, a lightning strike hits the lab's rooftop antenna, channeling high-voltage electricity into the glass jar and incinerating the brain just before Cory can commit murder.

While not the very first film to touch upon the concept, Donovan's Brain permanently popularized the "telepathic brain in a glowing tank" trope across American science fiction, paving the way for later parodies and homages in pop culture. The movie became infamous for its sensationalized promotional taglines, most notably on theater posters reading: "A dead man's brain in a hidden laboratory told him to... KILL! KILL! KILL! KILL! KILL!" Curt Siodmak's original book was adapted multiple times, including The Lady and the Monster (1944) starring Erich von Stroheim, and a later European production titled The Brain (1962).