Time Out says
Vintage Hitchcock, with sheer wit and verve masking an implausible plot that spins out of the murder of a spy (Fresnay) in an equally implausible Switzerland (all back-projected mountains), leaving a pair of innocent bystanders (Banks and Best) to track his secret - and their kidnapped daughter - in a dark and labyrinthine London. Where the remake had Doris Day maternally crooning with fateful foreboding, sharpshooting Best simply grabs a rifle and gets after the villains. Pacy, exciting, and with superb settings (taxidermist's shop, dentist's chair, mission chapel complete with gun-toting motherly body, shootout re-enacting the Sidney Street siege, terrific climax in the Albert Hall), it also has nice villainy from a scarred, leering Lorre (here making his British debut). At two-thirds the length of the remake, it's twice the fun. (From an original story by Charles Bennett and DB Wyndham Lewis.
Cast and crew