Mazes and Monsters (1982)

Bound together by a desire to play “Mazes and Monsters,” Robbie and his four college classmates decide to move the board game into the local cavern. Robbie loses his mind, and the line between reality and fantasy fuse into a harrowing nightmare.
Steven Hilliard Stern
Tom Hanks, Wendy Crewson, David Wallace, Chris Makepeace, Lloyd Bochner, Peter Donat, Anne Francis, Murray Hamilton, Vera Miles, Louise Sorel, Susan Strasberg, Eric Fink, Chris Wiggins, Clark Johnson, Tom Harvey, James O’Regan, Kevin Fox, Angelo Rizacos, Kevin Peter Hall, James Bearden, Marshall Jay Kaplan
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