Goofs

As the doctor is trolling for a new body, his car changes. He starts off with a 1959 Ford convertible (retractable hardtop) with a light colored interior and factory accessory spotlight. When he arrives at Doris' (the "poser") house, his car, although still a black 1959 Ford, now has a dark interior and a fender mounted mirror.

When the doctor loses control of his car and is thrown out, he rolls down a steep hill. He sits up and sees the burning wreckage of his car. He gets up and staggers over to it. Except he runs on down the hill instead of back up the hill where he should have.

When Cortner is in the stripper bar, we see a party of people get out of their booth and leave, and Cortner sits there. When he gets up to go into the back room, there's a cutaway shot of that same party of people sitting in the booth again.

The film ends with the title "The Head that Wouldn't Die" instead of "The Brain that Wouldn't Die."

When the doctor is sitting visiting the blonde stripper, to his back is a bare wall with two hanging cats and to his left is a wall with flowered wallpaper and a huge mirror with photos. When the brunette stripper comes in she stands in front of the mirror. Words are exchanged and the doctor leaves. More words are exchanged and the blond slaps the brunette. Not only does the brunette have the bare wall behind her now, the cats have changed position as well.

Even were it possible to keep a severed head alive by ensuring enough oxygenated blood is circulated through the brain (as it appears to be, here), it would still be impossible for Jan to speak without lungs or vocal cords.

Common sense will tell you that when somebody is performing an operation (say, an open heart surgery, or more specifically, in the film they're performing an operation to stimulate the patient's brain) the doctor(s) will get blood on them. Amazingly, Dr. Cortner comes out of the operation room spotless, as do the other doctors and nurses as well as the patient.

The close up of the brain operation in the beginning of the movie was lifted from The Black Sleep (1956). And as a consequence, no skull under the skin.

Even though Cortner is able to take Jan's head and keep it alive, there is no way she would have the full brain function that she has as her brain would have been starved of oxygen long ago.

After Bill leaves the strippers' changing room and the blonde stripper slaps the brunette stripper, the close-up of the slap shows an extremely hairy male stunt double's arm.

If you look closely at the lamp sitting on the end table near the window in the "upstairs" part of the country house, you'll see that the power cord actually leads "outside" through the window.

When the doctors are operating in the first scene it is really obvious that they are not really cutting anything.

One man subdues another using surgical tongs.

The man hiding behind the opaque glass wall is clearly visible and it is contrary to common sense that he would not know this.

During the accident, we hear the brakes screeching before Bill puts his foot on the brake pedal.

When Dr. Cortner approaches the crashed car being consumed by fire, he is confronted by a male hand (note the hairy wrist) which drops from sight when he touches it. The car's only occupant is supposed to be his girlfriend, Jan.

Kurt spends well over a minute in the Cortner living room, gushing blood from a severed arm. When Doris visits the Cortner house a few minutes later, she doesn't notice any blood on the floor or furniture.

No police officers ever show up at Cortner's residence to question him about his wrecked and burned car, nor about the burned corpse with the missing head.

When Jan and Bill are finally alone in the operating room at the beginning of the film, a shadow of the boom microphone is visible on the wall behind them on the right side of the frame, above their own shadows.