The Moment of Proof

Episode 12 (3x12)

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A man is conclusively linked to a series of murders at music venues by a shoelace with traces of his final victim's DNA on it. After two people are set upon at a music festival by attackers with the same description, police are in a race against time to find their man, but then a third assault at a nightclub leaves them a vital clue. Also today, coded information buried within a spreadsheet reveals the man responsible for a campaign of hacking and blackmailing that targeted businesses.