This unofficial remake of The 39 Steps was made shortly after an update of The Man Who Knew Too Much, which maybe gives an impression that Alfred Hitchcock was running short on inspiration. Though that proved illusory a year later when he changed everything with Psycho.
The feeling of repetition is amplified by Ernest Lehman's threadbare dialogue. Robert Donat and Madeleine Carroll (in the 39 Steps) traded infinitely more sophisticated sexual innuendo than Cary Grant and Eva Marie Saint, who share zero chemistry. The two stars don't even share neighbouring generations.
I love Cary Grant but he could have performed this in his sleep and at times appears to be doing so. The best performances are by James Mason and Martin Landau as an all time great double act of villains. And yet. This is still an exciting, chic thriller with some of the Master's most brilliantly constructed set pieces,
Of course there's the crop dusting scene which grows out of nothing in a rural wilderness to a stunning crescendo of action. The denouement on Mount Rushmore is cinema legend. There are weaknesses and the MacGuffin of the trafficking state secrets is horribly perfunctory. But as a summation of Hitchcock's cinematic art, it is a triumph.