Mark Steyn writes:
Longtime readers know I’m enormously fond of the sexual crackle in the scenes between Cary Grant and Eva Marie Saint. But that between Landau and Mason is almost as good. The young actor told Hitchcock he’d like to play Leonard as homosexual – mainly because in the Chayefsky piece he’d been a burly, beery macho guy. Hitch wasn’t much for Method actors, but the notion tickled him, and it made sense: Why is Leonard so vicious toward Eva Marie Saint’s character? Because he wants to take her place in James Mason’s affections. How does he know she’s working for the Feds? “Call it my woman’s intuition,” he says. “Why, Leonard,” responds an amused Mason, “I do believe you’re jealous.” Moments later their relationship finds physical expression, albeit violently.
In North by Northwest, James Mason’s Vandamm does not want for minions, and almost all of them survive to the climax on Mount Rushmore. But Leonard is the one you remember – ever present, usually just behind Vandamm, invariably staring at him, often wearing a matching suit. That last was Hitchcock’s idea – that Leonard should have smarter suits than Cary Grant’s character. Don’t ask me why: It’s just one of those small details the director liked to throw in to prevent your assumptions about characters getting too predictable.