A midnight showing of a film in a movie theater; not necessarily at matinee prices, but called so to allow catchy alliteration. Usually, the film being showed is a cult classic (see also, cult film, cult), or a very strange B-movie. The audience is typically rowdy and interested in a good time.
Examples (many of the below examples were shown at midnight matinees at a nearby theater):
My own experiences with the midnight matinee include attending a film festival in Sacramento titled The Trash Film Orgy. Upon arriving at the theater (downtown was deserted for the moment), we entered the large crowd out in front. They crowd encircled a rather interesting spectacle. A man dressed as a circus ringleader was walking about and shouting about "Flipper Boy". Flipper Boy, I assumed, was the man covered in a black poncho (with small flippers attached) with a hockey mask on, rolling around on a skateboard. There also was a seedy looking woman dressed rather scantily, who would occasionally whip Flipper Boy, causing him to erupt in screams. We bought our tickets and entered . . .
Another man dressed as a ringleader was dj'ing for the production. He played some very strange, tinny sounding music (for example, a version of Rhapsody in Blue with electric keyboards, and Popcorn by Hot Butter). At the front of the theater was a large "idol" with cardboard flames spouting from its mouth. About five minutes before the show began, it began to talk, its eyes lighting up rather than its mouth moving. The host of the orgy, a man named "Francois Fly", came out and began shouting obscenities. There was a brief introduction (which included some wrestling) and the film was announced.
We were seeing THE INCREDIBLY STRANGE CREATURES WHO STOPPED LIVING AND BECAME MIXED-UP ZOMBIES, which fit with the rest of the orgy's offerings as it was an old, scratched up, very bad, Mystery Science Theater 3000 style movie. It was horrendous, a musical horror flick, replete with avant garde dance numbers. At the climax of the film, a group of actors in zombie costumes ran out into the theater, trying to scare all of us. All in all, the evening was quite enjoyable.
Other movies in the Trash Film Orgy included: