Wendy Knell and Caroline Pierce were both murdered by David Fuller in 1987, in Tunbridge Wells, Kent. For more than 30 years, their killers remained on a large scale, until advances in technology led to the adoption of familial DNA techniques.
BBC Home Office correspondent Tom Symonds spoke with Noel McHugh, an investigative director at the National Crime Agency who advised the David Fuller investigation.
Mr Fuller is being sentenced at Maidstone Crown Court on December 15.
Let’s see how the police track him down.
Produced by Alex Dackevych
