 The screenplay is credited to Alec Coppel (qv) and  Samuel A. Taylor (qv), but Alec Coppel (qv) didnt write a word  of the final draft. He is credited for contractual reasons only.  Samuel A. Taylor (qv) read neither Alec Coppel (qv)s script nor  the original novel, he worked solely from  Alfred Hitchcock (I) (qv)s outline of the story.