The Tingler (1959)

A pathologist (Vincent Price) is doing research on fear. He notices that the spines of executed criminals are split open leading him to believe that terror, not the electric chair, is what kills them. When the deaf mute wife of a theater owner dies unexpectedly, he x-rays the body and discovers the culprit: The Tingler! He cages the creature for further research and determines that a) everyone has one of these in their bodies and b) you can keep them from killing you by screaming.

The Castle-gimmick was that some of the theater seats were wired to give the occupant a shock at appropriate times during the film. Presumably the appropriate time was when the tingler escaped into the theater (the one in the movie), they cut the house lights, and Price tells everyone to scream or else the tingler will get them. That might have worked.

Here's something cool. The movie is in black and white except for one of the scare scenes, where the blood is red. The effect worked but it kinda makes you wonder why they didn't film the whole thing in color. Also, the actors playing the young couple actually got married (kinda cool) then divorced (not so cool). The actors playing the older couple (the theater owners) both died eight years later in May of 1967 (totally uncool). The creature itself was modelled after a Velvet Worm. Wikipedia doesn't say if this species moves through the use of visible wires. Another interesting part is when the Price character wanted to feel fear (you see, he's super macho-brave and is never afraid), so he takes a hit of acid. The first time an acid trip was featured in a movie.

Typical William Castle. In a TCM Biography his daughter said of the film, the biggest obstacle for the actors was to not burst out laughing at the silly prop and absurd dialog. Typical Vincent Price rising above the source material. There was a background story about Price's philandering wife, or her sister dating his assistant (see above comment regarding a "young couple"), but it doesn't play much into the film except maybe to give Price an opportunity for biting dialog. A fair effort all-in-all. A well made, cheesy, B horror movie. AMRU 3.5.

"The tingler exists in every human being, we now know. Look at that tingler, Dave. It's an ugly and dangerous thing-ugly because it's the creation of man's fear; dangerous because... because a frightened man is dangerous."