Birmingham authorities struggle to explain why they disavowed their own findings about the Trojan Horse plot. But when Brian and Hamza make a discovery deep inside some court documents, everything suddenly makes sense.To get full access to this show, and to other Serial Productions and New York Times podcasts on Apple Podcasts and Spotify, subscribe at nytimes.com/podcasts. To find out about new shows from Serial Productions, and get a look behind the scenes, sign up for our newsletter at nytimes.com/serialnewsletter. Have a story pitch, a tip, or feedback on our shows? Email us at serialshows@nytimes.com