The late David Cornwell wore many hats. He worked for both MI5 – the UK's domestic counterintelligence agency – and MI6 – the British Secret Intelligence Service. He was also a bestselling spy writer, penning espionage thrillers under the name John le Carré. His life is worthy of a novel in itself – and documentarian Errol Morris achieves something like it with The Pigeon Tunnel, a deeply intimate final interview with Cornwell.

In the official trailer, released by Apple TV+, the author tells his interviewer: "I'll answer any question you wish me to answer, as truthfully as I can". The initial look sees le Carré speaking about recruitment for England's secret service, his own journey as a writer, and the concepts of betrayal and loyalty.

The documentary is an adaptation of le Carré's autobiography. Morris, an Academy Award-winning director, sat down with the writer to record interviews over the course of four days in 2019. The trailer features a blend of the conversations they had alongside archival footage and reenactments of the stories le Carré tells.

The Pigeon Tunnel is streaming on Apple TV+ on October 20.