This one is a damned curious British noir (some, including myself, would generally have that as an oxymoron, but I'm comfortable with the term here, as it really is precisely tapping into post-war malaise and other very recognisable Yankee genre tropes). Nice dialogue too, "He's not even a respectable crook, he's cheap, rotten, after-the-war trash" describing baddie Narcy (short for Narcissus after the Greek myth, well played by Griffith Jones).
Wild child RAF ace Clem (Trevor Howard) is too bored with civvy street after all the shoot-em-ups, Immelmans and ack-ack show. So he decides to try his arm at crookery and ends up with Narcy and his gang, Narcy needs a guy with class. Only things don't go so well so Narcy hangs a frame on Clem and takes his popsy. "What's 'e in for?" "Manslaughter - killing a cop" "That's not manslaughter, that's fumigation".
The rest of the film is the revenge story. It's all nice and dark up to a point, but gets rather too intricate for its own good and sprawls a bit, ending up feeling twenty minutes too long at 1 hr 40 mins. Due to the times there's not much scope for the violence that some scenes in this film pretty much demand according to the dictates of logic. The lack of the effect half of cause and effect makes the climactic scene absurd, and actually had almost the entire theatre at the Edinburgh Film Festival's revival screening in giggles. There's room for humour in a film like this, Hitchcock showed that well, but I think Cavalcanti over-eggs the pudding in the manner of Jon Farrow's American noir of 1951, His Kind Of Woman. The humour came in as a step change rather than equally spread in an even-toned master work. I may of course be in the position of being kind and assuming that the humour was intentional.