The basis of an innocent person becoming tangled in a snarl of conspiracy is at the hub of Hitchcock films such as The 39 Steps, Saboteur, North by Northwest and, most conspicuously in this case, The Man Who Knew Too Much, which encouraged Foul Play's opera house climax.
Foul Play is a deference to Sir Alfred Hitchcock, more than a few of whose films are alluded to throughout the film. The basis of an innocent person becoming tangled in a snarl of conspiracy is at the hub of Hitchcock films such as The 39 Steps, Saboteur, North by Northwest and, most conspicuously in this case, The Man Who Knew Too Much, which encouraged Foul Play's opera house climax. When Goldie, the obligatory blonde, is assaulted in her home, she rummages inside her knitting basket and nearly settles on a pair of scissors to protect herself, a citation of Dial M for Murder. As well, the plot embraces a MacGuffin, in the shape of the celluloid roll hidden in the cigarette pack.