This British comedy was a vehicle for the talents of Will Hay, Moore Marriott and Graham Moffatt, who had first performed together in Windbag The Sailor (d. William Beaudine, 1936) in which Hay played an inept sea captain.
Here, their characters are placed in a rural railway setting with Hay attempting to assert his authority as a new stationmaster, taking the name of Porter from a popular song ("Oh, Mr. Porter, whatever can I do?/I want to go Birmingham and/They've taken me on to Crewe").
The scene of Porter's arrival by coach parodies that of Dracula (US, d. Tod Browning, 1931): in both films, the locals warn a new arrival of fearful danger. In broader terms, this picture lightly reworks the idea of Arnold Ridley's famous comedy-thriller The Ghost Train, (already filmed twice, in 1927 and 1931) in which a phantom train is used to carry firearms.
However, it is not the plot but the richly humorous characterisations and dialogue, together with the charming atmosphere and sharp pacing of the film, that make Oh, Mr Porter! such a success. The station exterior was a real one about to be demolished and it is skilfully dressed by art director Vetchinsky, whose interior sets are also completely convincing.
Director Marcel Varnel kindles a rich interplay between Porter and his two insubordinate assistants that makes each believable and distinctive as characters. Their misdemeanours are petty and sympathetic, and Porter's refusal to give in to adverse circumstances becomes heroic.
Oh, Mr Porter! is full of moments to cherish - from Harbottle's first line, "Next train's gone!", to Porter's explanation of why wheeltappers tap wheels - but it also has many extended scenes of comic brilliance such as that in which the trio, having blocked the line in a shunting exercise, try to calculate how much time they have before the express is due.