The Prowler (1951 Joseph Losey)

What's Van Heflin up to? He seems a bit of a nutter. What's Evelyn Keyes up to? She seems somewhat nuts. Is she really married to a radio  broadcaster? And what's the prowler got to do with it?

Robert Thoeren and Hans Wilhelm provided the story which was screenwritten by Dalton Trumbo (then blacklisted, so not credited; also the voice of the DJ) and Hugo Butler.

Independent Horizon production (Sam Spiegel), shot by Arthur C Miller and scored by Lyn Murray, is intriguing and noirish enough to qualify for being one of Eddie Muller's Top 25, who adds this fascinating contextual detail:

Losey's political antagonists saw an insidious anti-American suggestion: pursuit of the perfect middle-class family could lead to derangement... its makers were trying to undermine American values. Screenwriter Hugo Butler and Losey were both named as Communist sympathisers and black-listed. Losey's incrimination oddly paralleled that of the Prowler: his career was derailed by an ass-covering informer who, Losey learned later, once had an affair with his wife...

('Dark City' Titan 1998.)

Memorable ending could be seen as delirious mix of lines, trajectory, angles and points of intersection.