"Contraband" (1940) was the second Powell-Pressburger collaboration, after 1939's "The Spy in Black". It is one of their lighter films, with a slight wartime propaganda element.
It stars Conrad Veidt as a Danish captain of a ship moored near London and Valerie Hobson as a passenger, an impudent young minx who steals a shore pass and rows ashore, where Veidt follows to bring her back, but when he finds her it turns out that Hobson is in fact on His Majesty's Secret Service and being pursued by some German secret agents. There's good chemistry between Veidt and Hobson, even though he's twice her age (almost literally- he was 47 and she was 23). Veidt is a commanding and charismatic presence and Hobson gives one of her freshest and most spirited performances, and is by no means difficult on the eye.
Powell had worked with Hitchcock and this is a fast-paced suspense movie in the mould of Hitch films like "The 39 Steps." Lots of good bantering dialogue between the two leads and a comedic element thrown in. The propaganda element is not very pronounced, and the mood is surprisingly light. All in all, a very enjoyable way to pass an hour and a half.