Lew Ayres stars as a doctor who is summoned to help try and save the life of a man involved in a plane crash. He dies and it turns out the man was a very wealthy and cruel man named William Donovan.
Ayres character of Dr. Patrick Cory uses this chance as a way to further his experiments so he takes the dead man's brain and keeps it alive in a special tank. His wife Janice (Nancy Davis) does not approve, but goes along with the experiment anyway. Gene Evans is Dr. Schratt who helps Cory, but again reluctantly.
Over time the brain gains power and starts to possess Cory who "becomes" Donovan and continues his nefarious business affairs.
I like this film a lot and always have. it is one of many adaptations of the Curt Siodmak story, and to me it is the best one. I was both surprised and happy to see Kino bring this out on Blu-ray, an I have never seen it look better than it does here.
If you like 50's sci-fi, then I can easily recommend this little gem that also stars Steve Brodie.