The investigation into the murders of two Leicestershire schoolgirls between 1983 and 1987 led to a groundbreaking use of DNA fingerprinting, developed by DCS David Baker and Dr Alec Jeffreys. A local teenager initially confessed to one of the murders, but was cleared through DNA evidence, prompting Baker to launch the world's first DNA manhunt, testing over 5,000 local men to find the killer.

The brutal murder of 15-year-old Lynda Mann in a quiet Leicester village in 1...