Hitchcock's first undeniably great film, and the standard against which all comedy thrillers are still judged.
Robert Donat as Richard Hannay is the paradigm of the director's wrong men, and he is superb. Assumed guilty by the press, public and the police of a murder he didn't commit he is compelled to escape north by train. Madeleine Carroll is the prototypical chilly Hitchcock-blonde, handcuffed to Donat as he attempts to clear his name. Their screwball romance is dynamite.
The film is only very loosely based on John Buchan's rather anaemic novel, and most of what was great about the film was added by the director and in Charles Bennett's witty adaptation and script. The episodic structure is bursting with classic scenes, and characters you really care about, far more than is typical with this genre. Like Peggy Ashcroft as the crofter's wife, living a remote life with an abusive husband. The occasional kindness of strangers who ease Hannay's escape make the film gently moving and the Scottish locations are pleasingly evocative.
The only weakness is a rather contrived MacGuffin, but it hardly matters. Hitch's camera is matchless. It's my number one out of everything he made.