This write-up is for , the final interview and cinematic memoir of the legendary spy novelist John le Carré (David Cornwell), directed by Academy Award-winner Errol Morris . Overview
The title refers to a bizarre contraption used in British pigeon shooting: a long, narrow, dark tunnel with a trap door at the far end. Live pigeons are placed inside. When the trap opens, the birds fly frantically toward the light, only to be shot by marksmen waiting outside.