NEW YORK – The stars aligned at this year’s British Academy Film Awards, where Michael B. Jordan, Leonardo DiCaprio, Timothée Chalamet, Ethan Hawke and Jesse Plemons were competing for best actor.

But the surprise winner was actually the guy with the fewest acting credits: relative newcomer Robert Aramayo, 33, who brings aching specificity and humor to “I Swear” (in theaters now), which is based on the true story of Tourette’s syndrome activist John Davidson.

“I never in a million years thought they were going to read my name out,” Aramayo says on a recent morning. “I didn’t ever think that my name would be considered amongst those names. … I still can’t really believe it. It was absolutely mental.”

The decades-spanning “I Swear” traces Davidson’s troubled upbringing in a working-class Scottish town in the 1980s, as he begins to experience inexplicable episodes of involuntary swearing and repetitive movements that rankle teachers, classmates and his own parents. He is eventually diagnosed with Tourette’s, and with the help of a family friend (Maxine Peake), he slowly learns how to manage his condition and find confidence in himself.

Davidson, 54, became the subject of numerous documentaries, and in 2019, made headlines for unintentionally swearing at Queen Elizabeth II while receiving an award for his advocacy work. But Aramayo had no idea who Davidson was until he read filmmaker Kirk Jones’ script for “I Swear.”