In 2014, a mysterious letter detailing a plot by Muslim extremists to take over Birmingham schools caused a national scandal. No one seemed to know, or even care, who actually wrote the letter – but in The Trojan Horse Affair, rookie reporter Hamza Syed and S-Town producer Brian Reed go looking for answers. Ash Sarkar asks them about their shocking findings and why the UK media's reaction to the podcast has been to close ranks and deny the evidence.