The Moment of Proof

Episode 6 (3x6)

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Blood spatters found on a trench coat belonging to a suspect in an unrelated case of armed robbery links a callous killer to the murder of a wealthy pensioner. The police find just a business card and a cigarette butt at the crime scene, but then a detective spots the coat at the suspected robber's house and decides to run blood tests on a hunch. Also today, a detective's dogged approach pays off when he proves that a light aircraft that crashed, injuring three people, was too heavy for take-off.