It starts the same way... A seemingly innocent message from someone who appears to be a young woman: ‘Can I tell you a secret?’ But as this six-part podcast explores, people are rarely their true selves online – and one man took it much further. What happened when this cyberstalker wreaked havoc across the internet and ruined people’s lives. And why did he do it?

Can I Tell You A Secret - a Guardian podcast series about obsession, fear, and the lives we lead online