In 2012, the body of Federica Mangiapelo was found by a lake in Italy. The coroner declared it a natural death, with the main suspect in the case claiming he was nowhere near the scene. But one tiny organism, invisible to the naked eye, proved otherwise.

Dr Paola Magni is a pioneer in aquatic forensics, a highly specialised and innovative form of criminal investigation. In this episode hosted by Kathryn Fox, discover how everything from plankton to barnacles can help bring criminals to justice and provide crucial answers to grieving families.

If you or anyone you know needs help:

• Lifeline (Crisis support and suicide prevention) 13 11 14
• 1800 Respect (National sexual assault, family and domestic violence counselling line) 1800 737 732
• Men's Referral Service (National counselling, information and referral service for men looking to change their behaviour) 1300 766 491
• Full Stop Australia (National violence and abuse trauma counselling and recovery Service) 1800 385 578

See omnystudio.com/listener for privacy information.