Speaking of his reluctance to become a leader of any kind of political movement, John Lennon once said: “I’ll always show my genitals or something, which prevents me from being Martin Luther King or Gandhi and getting killed.” As The Killing of John Lennon shows, his plan didn’t work.

This is a well-researched, fact-based drama about Mark Chapman, the man who, in December 1980, murdered Lennon. Since we know what happened, all that’s left for the writer and director, Andrew Piddington, to explore is the mysterious: Why? And this he does with great gusto, delving deep into the murky mad swamps of Chapman’s mind. The film moves between the tense realism of a countdown to a killing and flights of dark fantasy.

The challenge for Piddington is to make a narcissistic nobody like Chapman an interesting character. Yet, as the scenes with his wife and the strangers he comes into contact with show, that’s impossible. Without a gun, he could still bore a man to death. Unlike famous killers such as Charles Manson, he wasn’t scary. Unlike Lee Harvey Oswald, he wasn’t mysterious. Chapman was just cold. It’s the sheer bland ordinariness of the man that Jonas Ball, a newcomer, manages to capture so well.

The best thing about the film is that it successfully challenges the Chapman story as it is conventionally told. For starters, we see he was not your typical isolated, rootless young man. He was not abused as a child or tormented as an adult. Chapman, who lived in Hawaii, had a job, a wife and a mother who cared for him. Since killing Lennon, he has come to symbolise the dark side of modern celebrity: the fan who goes over the edge and becomes the fanatic who will kill for his own 15 minutes of fame. Yet, though Chapman came to enjoy his notoriety, that was not his prime motive.

His story really begins, of all places, in a public library. There, desperate to find an identity and have a mission, he comes across JD Salinger’s The Catcher in the Rye. He reads it and undergoes a kind of born-again conversion, seeing himself as the novel’s protagonist, Holden Caulfield, an alienated 16-year-old who hates phonies. For Chapman, Lennon is the ultimate phoney, because he asked the world to imagine having no possessions, then accumulated numerous homes and apartments.

So he decides to kill him and become the catcher in the rye.

But the man Chapman most resembles is not the precocious, gentle Caulfield, but the crazy Travis Bickle from Taxi Driver. (At one point, we even see him mimic the iconic shot of Bickle pointing a gun-like finger at the side of his head.) Piddington conveys the mean streets of Chapman’s collapsing mind, a feverish landscape of violent longing and sweaty mutterings about the scum that needs to be washed away.

The film works best at these moments of mental instability. What’s missing, however, is a sense of the private Chapman. Although we hear a voiceover of his actual words, you never really get a sense of him off camera, as it were. I could have done with a few more revealing personal details. For example, everyone thinks of Chapman as a Beatles nut, when in fact he was a Todd Rundgren fanatic. And we never really get to understand him. There was no shortage of angry, alienated young men in America at that time, so what was it about Chapman that made him turn to murder?

The film ends with a curious irony. Chapman must remain in solitary confinement for ever, to protect him from the peace-loving Lennon fans who want him dead.

15, 110 mins

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