This week, Iain digs into a 1992 murder case that took place in Lincoln. When two people are found dead having been attacked with an axe, police begin an unusual investigation to catch the killer. An investigation that involves paint fragments, an infrared light machine, and a 3,000-mile trip around Europe. Murder They Wrote with Laura Whitmore and Iain Stirling is available weekly on BBC Sounds. Subscribe now so you never miss an episode. Email us at [email protected].