Cert - 15

Run-time - 2 hours

Director - Kirk Jones

John Davidson (Robert Aramayo) grows up with Tourette syndrome in a world that doesn't know about or understand it, with occasional faces helping him to cope and educate people.

I Swear's opening scene acknowledges, as does the main character later in the film, that it's ok to laugh. Yes, there will be some occasions where John's (Robert Aramayo) tics lead to serious misunderstandings with people, or bring him down as he struggles to cope - one particular scene where verbal tics echo around a room where he's isolated himself from everyone else makes for one of the most effective moments in the film - but, there are still moments where humour can be found without mocking.

Based on the autobiographical book of the same name, John is diagnosed with Tourette syndrome shortly after starting secondary school in the mid-80s (young John played by Scott Ellis Watson). Growing up little is known about it, and therefore he is often labelled as a bad child for something he increasingly cries out that he can't help.

As the 90s arrive, an older John is still at home with his mother (Shirley Henderson - as the most hateable character of the year, and bear in mind Sean Penn's Col Steven Lockjaw currently scowling in One Battle After Another), his father having left when he was young.

After meeting an old friend and being invited back for tea, John finds himself welcomed into a home where he doesn't have to apologise for anything he can't control.

Finding a calmer environment, led by Maxine Peake's Dottie (Peake on truly wonderful form as a beam of kindness often stealing the show from Aramayo's impactful performance), John starts to go out into the world more, gradually dosing down his medication, with more freedom but many obstacles in the way.

Community centre caretaker Tommy (Peter Mullan) encourages John, especially as a court trial for a bar fight started after a physical tic knocks a glass out of someone's hand, to teach and educate people about Tourette's, however he needs to understand it himself.

Both Tommy and Dottie help in this development and change and there's a sense of welcoming from both characters in the central figure's journey. A journey which amongst the struggle, largely thanks to the reception such characters give him, has some warmth, and, again, humour, to help things along.

Yet, for all the talk of discussion that the film contains the best moment is perhaps one of prolonged silence. As the sequence unfolded I found myself in a sustained state of surprise.

As the moment continues, and enters brave depths for John calling back to an earlier conversation, emotions rise and much of what has come before comes back to the fore in this striking moment, particularly for John.

There's a welcoming nature to I Swear thanks to the way in which it establishes itself in the opening scene. Letting us know that there will be humour and lightness amongst the drama, and it helps to keep things going.

Four stars