The screen rights to Levin's stage play Deathtrap were purchased by Warner Brothers less than a month into its original Broadway run, for a record-breaking 1.5 million dollars. Levin had initially contemplated writing the screenplay himself, telling 1978's Christian Science Monitor:
Ultimately, Levin passed, and Warner's contract – which required they wait four years before releasing their film version (an unfathomably long stretch for a standard play) – premiered just weeks after that waiting period expired. And just three months later, Deathtrap's four and a half year Broadway run ended. (At that time, the existence of a cheaper movie ticket alternative to its far-costlier Broadway counterpart was a virtual death sentence for any play.)
No fault can be found with the 1982 film's Michael Caine/Christopher Reeve-led performances, its direction, or its baroque-flavored Johnny Mandel musical score. Levin was not however enamored of screenwriter Jay Presson Allen's newly-imagined opening and ending scenes, telling legendary talk-host Larry King in 1991:
Moreover, Levin was not thrilled with Allen's toning-down of the comedy half of his comedy-thriller. Allen told the New York Times: “Ira Levin's script is very, very clever and a little profligate. He gives you six laugh lines in a row. And reversal, reversal, reversal. When you take his script and go down the page, there's feed line, laugh line, feed line, laugh line. A film audience won't buy that. There must be reality about the situation."
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Deathtrap was one of the inspirations for 2019's Knives Out.
