This is an odd little film from some veteran British talents. Roy Ward Baker (Quatermass And The Pit) had started out at Gainsborough Studios, becoming assistant director to Hitchcock on 1938's The Lady Vanishes but only graduating to the top job after returning from the war. This break came through novelist Eric Ambler, who he'd worked under in army photographic units and who fixed Baker up to direct the adaptation of his own novel The October Man (1947). The pair would reunite for both Highly Dangerous and for 1958's Titanic story A Night To Remember, which won a Best Foreign Film Golden Globe.
Of the three films, Highly Dangerous is the least celebrated, but it remains a memorable, intriguing novelty which combines offbeat comedy with an unusual Cold War thriller yarn. It stars Margaret Lockwood, another great of the era's British film industry, having come from the stage to appear in such films as Lorna Doone (1934), The Lady Vanishes and The Wicked Lady (1945).
Lockwood plays Frances Gray, a British entomologist who is persuaded by the government to go to an Eastern Bloc country as a spy. She reluctantly accepts, hoping the posting will liven up her life. The commies, it seems, are breeding bugs - both bacteria and insects, with the latter to be used as carriers in fiendish germ warfare plots.
On her arrival, she doesn't speak the language and so sticks out. Her cover is nearly blown, and her position becomes even more precarious when her contact is murdered. The plot thickens - and becomes somewhat confusing - when a drugged Frances starts to believe she is the heroine of a radio thriller serial, and concocts a plan with American journalist Bill Casey (Clark) to enter the secret labs and steal evidence.
It's hard to work out what's going on with Frances when she's in this state, and her alter-ego's heroics strain credulity somewhat, but the sheer novelty of the plot is fun. Indeed, it's hardly supposed to be a heavyweight endeavour and all the cast members, from Lockwood and Clark to supporting players Marius Goring (A Matter Of Life And Death) and Naunton Wayne (The Titfield Thunderbolt), are highly watchable.