Question: Who was the director of the 1968 Metrocolor Cold War era suspense and espionage film that had its screenplay written by the novelist who wrote under the pseudonym Ian Stuart?
Sentence (from "Ice Station Zebra"): The screenplay by Alistair MacLean, Douglas Heyes, Harry Julian Fink, and W. R. Burnett is loosely based upon MacLean's 1963 novel of the same name.
Relevant evidence: No