Documentarian Errol Morris has made a career of understanding truth, often employing his unique style of interviews to allow his subjects to speak for, and reveal, their own perspectives on reality. He’s interviewed men at the heights of power in his films The Fog of War and The Unknown Known and people in the lowest of social castes in Vernon, Florida and Gates of Heaven. His series First Person and his film Fast, Cheap and Out of Control allowed experts in a variety of fields and experiences to speak directly to the camera about their niche knowledge sets. His methodology is built on allowing subjects to reveal something about themselves to the audience.

Famously, a career-defining moment was when Morris’s film The Thin Blue Line freed a wrongfully convinced man, which became in many ways a template for the future true-crime genre of films and podcasts. That wasn’t his goal in making The Thin Blue Line, and what has always made his documentaries so fascinating is that his agenda is uniform across them: Whether he’s exploring the life of men whose choices led to the deaths of hundreds of thousands, or a man who knows too much about naked mole-rats, Morris’s films are always about understanding the world as his subjects see it, even if that world is contradictory, complicated and controversial.

The Pigeon Tunnel — now streaming on Apple TV+ — feels like one of the most direct dissertations on the concepts of truth and fiction of his entire career. That tracks with his subject this time around, the late British novelist David Cornwell, better known as famed espionage novelist John le Carré. Cornwell worked for the British Security Service in the post-World War II world before turning his experiences into the basis of his novels, which included The Spy Who Came in from the Cold and Tinker Tailor Solider Spy. His novels, which blended the reality of his experiences with a morally ambiguous view of spies and their profession, ran contrary to the much more sensationalist characters like James Bond.

Morris interviewed Cornwell in late 2018, and The Pigeon Tunnel is classic Morris in its construction, supplementing their discussion with re-enactments, archival footage and even a new score by composer and longtime collaborator Philip Glass. Although the film is ostensibly based on Cornwell’s autobiography of the same name, Morris eschews a traditionally biographic narrative in favor of a wide-ranging conversation between the two about what separates truth and fiction, as seen by a man who spent his life blurring the two.

Before he was a spy, Cornwell learned the art of masks from his father, Ronald, a confidence artist who only felt alive while swindling marks. Once David Cornwell became an intelligence officer, he spent his days interrogating, investigating and running operatives in West Germany. His experiences in the field in the early 1960s ended when Kim Philby, a well-respected MI6 agent, was infamously revealed to be a spy for the KGB. Philby’s betrayal, as well as his professional experiences near the Iron Curtain, gave Cornwell a lifelong sense of anguish and cynicism about the decaying power of his government and the arbitrary, chaotic nature of historical “progress.”

Cornwell’s perspective on the world makes him an ideal interview subject for Morris, particularly at this stage in the filmmaker’s career. The two are similar in age and experience, having spent their lives and careers extracting stories from the truths they’ve witnessed. In Cornwell’s case, he turned truth into outright fiction; it’s clear by the end of the film that Morris contemplates the nature of his work and the stories he’s told as well. Morris has always been self-effacing about the nature of his documentary work and bluntly honest about the nature of his role as a storyteller, looking past the common view that documentaries need be rote recitations of facts or a vérité exposé on a subject.

What does it mean, seeking the core truth of a subject? Of what perspective are we even capable? It’s a question embodied by the central metaphor of the film, which takes its title from a story Cornwell relates. He witnessed a group of wealthy, sporting men on a beach, their guns at the ready, as a flock of pigeons were loosed from their cage, flying from captivity through a tunnel designed to direct them in the direction of their murderers’ gunsights. Are we the people waiting? Are we the pigeons?

At this point, familiar audiences should know what to anticipate from a new Morris documentary: He asks questions to interesting men and women as a means of learning something new, which often leads to more questions. The Pigeon Tunnel may not be a film destined to make headlines like some of his others, but its focus on the filmmaker’s core themes makes it a deeply satisfying watch for anyone who is a fan of his life’s work.