"The fly with the head of a man...! And the man with the head of a fly!"

Scientist Andre Delambre runs into some unfortunate circumstances when his latest experiment, a matter transporter, accidentally fuses his atoms with that of a common housefly. Andre ends up with the head and left hand of a fly, with his corresponding limbs on the insect.

While his frantic wife desperately searches for the fly with her husband's head and hand, Andre battles his new insect instincts to murder, and presumably eat, his wife.

"The Fly" is a classic! It has a great performance by Vincent Price as Francois Delambre, and unsettling effects. Most notably the final scene of the fly with the human head screaming for help, as it's menaced by a spider.

Here's the trailer!