Husband and wife sleuths sifted through a serial killer’s flat and found the possessions of people who would later turn up dead.
They were in the lair of a monster known as The Serpent – and the evidence they discovered would help bring him to justice.
Angela Knippenberg, who spoke six languages, translated all the diaries they found and carefully catalogued all of the items.
Then she and Dutch diplomat husband Herman handed the evidence to Interpol. They were a crime-fighting team, although Angela says you would not think so from the BBC’s new eight-part series, The Serpent.
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