Doctor Patrick Cory (Ayers) has been trying to keep monkey brains alive outside the body for some time. The day he succeeds, a plane crashes near his isolated home. The lone survivor--multi-millionaire W. H. Donovan--is brought into Cory's operating theater, but dies on the table. Donovan's brain, however, is still alive. There's only one thing to do: Over the objections of his wife Jan (Davis), and assistant Frank (Evans), Cory removes Donovan's brain and connects it to his apparatus.

Later, when visiting town to answer questions about Donovan's death, Cory is accosted by a nosy photographer, Herbie Yocum (Brodie). To allay his suspicions, Cory allows Yocum to photograph the table where Donovan died; Yocum surreptitiously photographs the bobbing brain as well.

As the brain thrives, absorbing nourishment, Cory decides telepathy is the way to communicate with it. After learning all he can about Donovan--who scorned taxes, suffered from a kidney ailment, etc.--Cory closets himself with the ever-growing brain, willing it to reach out to his mind. As he tires, a connection is made: Possessed, the right-handed Cory scribbles a cryptic note with his left hand.

Convinced he's succumbed to self-hypnosis, Jan and Frank beg Cory to stop the experiment, but instead Cory follows the note's instructions and travels to Los Angeles, Calif. There he resumes the dead man's life, drawing off secret bank accounts and blackmailing a high-placed "Washington connection" into papering over Donovan's tax evasion. When the pesky Yocum tries blackmailing Cory in turn, Cory sends him back to be killed by the monstrous brain at close range.

Even as Frank and Jan decide they must act before Donovan kills them, Cory/Donovan rushes home to eliminate the two people standing in the way of his domination. Terrified, Frank and Jan have one desperate chance to destroy Donovan before it's too late.

Living brain, dead movie

It might be argued that the worst film directors are not the Ed Woods of the world, but the Hollywood hacks--the people who take someone else's ideas and, in filming them, drain them of all blood and vigor. An apt example is Felix Feist's version of Curt Siodmak's novelDonovan's Brain. The film lacks both tension and momentum; it simply cuts from one lifeless tableau to another until it runs out of plot and ends.

The banality begins with the casting. Lew Ayres, best known at the time as Dr. Kildare, is too genial to play Cory. By casting Ayers, the creators stripped away Cory's obsession and introversion--personality traits crucial to his motivation--leaving behind an avuncular country doctor with a brain in his fish tank. At his side is an emotionally empty Nancy Davis, who has no on-screen presence even in close-up. Her one chance to show mettle--confronting Donovan in the climactic scene--is a let-down, and is immediately undermined by what happens next.

Certain elements from the novel are carried over into the movie, only to be badly mishandled. It's simply unbelievable that Cory would allow Yocum into the room where the brain is; sure enough, he "accidentally" gets a shot of the brain, while Cory stands by stupidly. Frank's alcoholism is shown, but since it's not used as his motivation to prove himself by defeating Donovan, it seems pointless. The subplots involving Donovan's son and daughter aren't used, but the characters are; they wander in and out of scenes like tourists given walk-on roles.

By sheer force of its root concept, Donovan's Brain retains some appeal. But it stands mainly as an illustration of how mangled an idea can get when it's adapted to film.