Who is Sergei Skripal? The former Russian spy was poisoned by Novichok in March 2018, but until now very little has been known about him, his life in England, and his mysterious past. His friend and neighbour tells the Inquiry what he was like and how they became close. Plus, the BBC‘s Security Correspondent Gordon Corera describes Sergei’s life as a spy in Russia, and reveals how he ended up in Salisbury. This episode was made by Marie Lennon, Andy Howard, Tom Ryan & Dan O’Brien. Executive production by Mary Sanders and Naomi Wordley.