Many relationships have tricky patches, with couples struggling for money or over the children. But there’s a spark in this story that takes us from the Lucan’s glamorous society wedding to Sandra Rivett being murdered, Lady Lucan attacked and the children swept away. And it grips us.

Alex von Tunzleman hunts for what triggers this story, delving through a box of Lucan’s possessions not seen for decades. As she discovers cheque stubs, invoices and letters from the bank, she sees the reality of what life was like behind the Lucan’s veneer of respectability: a world of debt and alcohol, gaslighting, late night calls and stalking.

Producer: Sarah Bowen