The African Queen (1951)
A pleasant, temperate romantic adventure about a missionary (Hepburn) and a steamboat captain (Bogart) who set out on a journey to sink a German gunboat by very provisional means in German East Africa at the outbreak of WWI. The combination of location and studio shots are executed quite nicely, and the picture still doesn't look half-bad even after all these years. It is only hampered by a slight but persistent aura of affectation running through it, despite the two stars' considerable – albeit completely asexual – chemistry. Luckily, the obvious shortcomings are not enough to ruin neither the fun or the rather thrilling ending. Bogart won the Best Actor Oscar for his work, inexplicably edging out Marlon Brando in A Streetcar Named Desire.