This is Alfred Hitchcock's first entirely successful film. It combines the thriller with screwball comedy to create a new genre. Robert Donat is the model for many of the director's wrong men. Madeleine Carroll is the prototype Hitchcock-blonde. The chemistry of their flirtatious crosstalk is dynamite.
The narrative is only loosely based on John Buchan's rather anaemic novel, and most of what was great about the film was added by the director and Charles Bennett's witty adaptation and script. Donat is presumed guilty by the press, public and police of a murder he didn't commit and is compelled to escape north to Scotland by train
He must clear his name with the impediment of being handcuffed to a beautiful, but unsympathetic woman. 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 a crofter's wife, stuck in an isolated cottage with an abusive husband.
It's the kindness of strangers to the innocent man which makes the film gently moving. The support cast is excellent, but the stars are a sensation. The only weakness is a contrived MacGuffin, but it hardly matters. The Master's touch is sublime. This is my favourite Hitchcock film.