Yes, I have watched my second film this year - and June isn't even over yet!
This is a 1964 film starring William Holden, Capucine, the Japanese actor Tetsuro Tamba and a young Susannah York, directed by Lewis Gilbert (whose next two films were Alfie and You Only Live Twice). It is set during the Malayan insurgency of the early 1950s, with Tamba playing the insurgent leader, Holden the maverick American, Capucine the woman who has (by implication) been the lover of both, and York as the daughter of the newly arrived British governor. Given that somewhat clichéd setup, it does what it does rather well. I was struck that for a film of the Cold War era about an overtly Communist insurgency it was notably unsympathetic to the British colonial administration; also both female leads play sexually confident characters who are frankly more interesting than the men. The music, by otherwise mediocre composer Riz Ortolani, is rather good the first couple of times you hear it (though suffers from too much repetition).
I actually bought it because I had seen in my grandmother's memoirs that my late aunt was an extra in some of the British colonial crowd scenes; I didn't actually spot her, but I'm bad at faces (and anyway this was several years before I was born).