Curtains is parody of 1950s "whodunnit" theater mysteries, where a lone detective, Lieutenant Frank Cioffi, investigates a series of murders that take place place behind the scenes of a fictional 1950s cowboy musical, Robbin' Hood. The cast of Robbin' Hood is forced to stay inside the theater while Boston police detective Frank Cioffi unravels the mystery, getting involved with the show and falling in love with ingenue Niki Harris in the process.