Actor Mark Wahlberg was supposed to be aboard one of the planes that crashed into the World Trade Centre on 9/11, but a scheduling change meant that he fortuitously ended up missing the doomed flight.
Some years later, his musings in an interview for Men's Journal on what might have transpired had he actually taken the flight go some way towards explaining Wahlberg's strangely self-aggrandising role in his new movie, Patriots Day.
The film is based on the events of the 2013 Boston Marathon bombings, in which the Tsarnaev brothers detonated pressure cooker bombs close to the finish line, killing three and injuring hundreds more.
The film, directed by long-time Wahlberg collaborator Peter Berg, professes to be a painstaking reconstruction of the fateful day's events and the city-wide manhunt that followed. Characters, locations, and events, for the most part, are depicted with impeccable detail.
But for a movie that has taken such great pains to be authentic, and exhaustively consulted victims, law enforcement professionals, witnesses and investigators, Wahlberg's casting defies reason. Sgt Tommy Saunders, played by Wahlberg, does not exist.
Nevertheless, Wahlberg's fictional composite character miraculously appears at every key juncture of the film. He's at the finishing line when the bombs go off. He helps the victims and directs the first responders.
He maps out Boston for the FBI. He responds to the Tsarnaev brothers' carjacking victim at the gas station. He's involved in the Watertown gun battle. And, finally, he has his gun squarely aimed at the younger Tsarnaev, as he emerges from hiding under the boat.
If this film is a testament to the bravery of Bostonians, as it claims to be, then why the need for a make-believe hero to take so much of the credit? It is difficult not to see this as a vanity project for Wahlberg.
The milk incident
For a film that claims to rely so heavily on the documentary evidence, the narrative is riddled with inaccuracies.
For example, in a scene shortly after the bombings, the two brothers are seen watching news coverage of the event from their apartment. Tamerlan's wife, Katherine Russell, interrupts them to complain that Dzhokhar has bought the wrong milk from the convenience store.
After a brief argument between the brothers, Tamerlan sends his brother out to exchange the milk. The film then cuts to actual CCTV footage of Dzhokhar rushing into the Whole Foods store to swap over the milk.
In reality, Tamerlan drove his younger brother to the store and waited in the car outside while Dzhokhar bought the milk, realised he had made a mistake and promptly returned inside to exchange it.
I'm not sure why Berg chose to alter this episode. It might seem fairly inconsequential - but may have something to do with the desire to show Tamerlan's wife as having prior knowledge of the bombings.
Making a film about a recent well-known tragedy cannot be an easy undertaking. There will always be questions around timing and decorum, or the tension between remaining respectful to the memory of victims and survivors, and the commercial exploitation of tragedy.
On balance, Patriots Day negotiates these challenges fairly successfully. Berg has crafted a tense thriller that manages to brilliantly document what happened, capturing the horror of the bombings, as well as the forensic investigation and manhunt in its aftermath.
But crucially, there is almost no introspection on the how or why. Instead, in the end, the audience is only left with Wahlberg's cheesy jingoistic epilogue, to restore some sort of moral clarity in the wake of what they have just witnessed. But perhaps that is the point of making these sorts of films.
• Akil N. Awan is Associate Professor in Modern History, Political Violence and Terrorism, Royal Holloway, University of London.