Plot
In 1983, 12-year-old John Davidson lives with his working class family in Galashiels, a town in the Scottish Borders. With aspirations to become a football player, John begins his high school term at Galashiels Academy. After hearing that a scout will assess his skills as a goalie, John begins experiencing episodes of tics and uncontrollable echolalia. The head teacher responds to this by whipping John's hand with a belt. This injury and his tics mean he performs poorly at football, much to the disappointment of his father. John is banished from the dining table by his mother after spitting and soon after he and his siblings are told that their father has left. John, distraught, attempts suicide by walking into a river, but is quickly rescued and wakes up in hospital.
In 1996, John at 25 years old is still living with his mother and is officially diagnosed with Tourette's syndrome. There is no known cure and John is medicated, but his tics remains an embarrassment. Murray, a friend of John's from school, returned to town from Australia after his mother is diagnosed with liver cancer. Murray invites John over to his house for dinner, which John does his best to avoid. Dotty, Murray's mother and a mental health nurse, senses John's discomfort and asks him about his medication. She informs the family that she wants John to stay with them.
John is weaned off his medication and told by Dotty to never apologise for his tics when around people who know his behaviour is uncontrollable. Murray brings John to a nightclub where he dances and chats with a woman, but in a ticcing episode he slings a drink out of another man's hand, and a brawl breaks out. John is remanded overnight and Dotty says that he will be tried on assault charges.
Dotty asks if John would like a job at the local community centre as the elderly caretaker's assistant. The caretaker, Tommy, shows John around and does not react to any of his outbursts, until John smacks Tommy's dog. John excuses himself, assuming that he has ruined his chances. Murray's family surprise John at home, saying that not only did he get the job but that the growth on Dotty's liver has been discovered to be benign. John is sent to collect a takeaway to celebrate but is attacked by two thugs in the street after calling a woman a 'slut' in an uncontrolled outburst. John is once again in hospital, this time with Dotty at his side, who assures him that the job will be waiting for him once he recovers.
John settles into helping Tommy the caretaker, who shares his view that it's not his Tourette's which causes problems, but rather other people's lack of awareness about it. John's trial date arrives, but he is unable to finish the oath without swearing at the judge, who removes him from the stand. Tommy, as character witness, defends John's behaviour as uncontrollable, saying that if a blind man had spilt the drink at the club then matters would not have escalated. The case is dismissed. John goes to visit Tommy at home afterwards and finds the man's body on the floor, having collapsed. John assumes that he will have to leave his job, but he is told that he has actually been promoted.
One day, a family from a local hospital is referred to John to meet up with their daughter, who is also struggling with Tourette's. Through this realisation, John starts hosting Tourette's workshops at the community centre, and later gives talks at schools and police stations to raise awareness for the condition. This eventually leads to him being invited to Holyrood Palace to accept an MBE from the Queen in 2019. After receiving the award, John visits his mother to show it to her and explain why he had not invited her to attend. His mother apologises for being short-tempered with him in his youth.
In 2023, John is invited by researchers at Nottingham University to test a treatment device. He finds that it calms his tics, to the point that he remains quiet throughout the entirety of a visit to the university's library. On the train home he strikes up a conversation with a woman, demonstrating his growing confidence.
The film ends with footage of the real John Davidson, who was the subject of several BBC documentaries, starting with John's Not Mad , along with a postscript emphasising the importance of societal awareness in the continuing treatment of Tourette's.
Release
In February 2025, Bankside Films launched pre-sales for I Swear at the EFM; a promo shown to buyers in Berlin revealed the first-look image. [6]
The film premiered in the Centrepiece programme at the 2025 Toronto International Film Festival. [7]
I Swear was released in the United Kingdom on 10 October 2025. [8]
In October 2025, Sony Pictures Classics acquired distribution rights to the film in the United States, Latin America, Turkey, Portugal, Southeast Asia, South Korea and most of Eastern Europe. [9]
