Double Indemnity (1945)

Alone in his company's Los Angeles offices late one evening and under some distress, insurance salesman Walter Neff dictates an inter-office memo to his colleague, claims manager Barton Keyes, about killing one of his clients, a Mr. Dietrichson. Barton suspected that Dietrichson was murdered by his wife, Phyllis Dietrichson, who was claiming the double indemnity on her husband's accident insurance policy. Walter met Phyllis innocently enough - he was dropping off auto insurance renewal papers for her husband - but quickly fell under her seductive charms. They were obvious to each other in their mutual attraction. After deducing that she was planning on killing her husband since she stated he was abusive and claiming the insurance moneys on a policy her husband would have no idea existed, Walter decided to go into cahoots with her so that he could help her craft and execute the "perfect" insurance policy, and plan and execute the "perfect" murder beyond Keyes' scrutiny, leading to them living in bliss together and with money. Beyond any slip-up in the plan, Keyes and Dietrichson's disgruntled daughter, Phyllis' step-daughter Lola Dietrichson, factored into their ability to pull off the plan successfully. Walter concludes his memo for its reason, which he considers more a confession.