In the film, Mr. Barron is hefty, large, tall man with grayish-white hair, white eyes with a tiny black pupil, and long, sharp teeth. He looks to be in his late fifties. He can turn his right arm into any weapon of his choice, such as a knife, axe, machete, etc.
In the film, Mr. Barron kills Abraham Portman, Jacob's grandfather, after Abe refused to reveal the secret location of Miss Peregrine's Home For Peculiar Children.
Later on, Jacob and the other peculiars rescue Miss Peregrine along with the other ymbrynes. Mr. Barron is killed by a hollowgast shortly thereafter.
He had to masquerade as a psychiatrist for three weeks.