But now the young actor has won a Scottish Bafta for his first role.
The Angels' Share star picked up the Best Actor in Film award at last night's glittering Bafta Scotland ceremony in Glasgow, fronted by showbiz luminaries such as Brian Cox, Rory Bremner and The Inbetweeners star Joe Thomas.
Brannigan, who grew up in the east end of Glasgow with heroin-addicted parents and himself became drug-dependent, spent time in prison. However, he turned his life around and was selected to audition for the film while working as a football coach for a Strathclyde Police community initiative.
The Angels' Share, directed by acclaimed filmmaker Ken Loach, was Brannigan's first acting role. But since making the whisky heist comedy he has gone on to work with Hollywood star Scarlett Johansson in alien abduction sci-fi film Under The Skin.
Glasgow-born Paul Laverty, The Angels' Share writer, won the Best Writer award for his screenplay.
Sitcom veteran Gregor Fisher won the Best Actor/Actress in Television award for his performances in Rab C Nesbitt. Fisher was up against his Nesbitt co-star Elaine C Smith and Iain de Caestecker of Young James Herriot for the award.
Meanwhile, comedy legend Billy Connolly was awarded for his Outstanding Contribution to Film and television, speaking to the audience via video.
But while it was expected the Best Comedy/Entertainment Programme award would go to Connolly's natural successor Kevin Bridges, it went instead to Mrs Brown's Boys, the hit BBC One sitcom starring Dublin-born Brendan O'Carroll.
It may surprise some that an Irishman and his co-stars picked up a Scottish award but the series is, in fact, a co-production between BBC Scotland and O'Carroll's own company, BocPix. O'Carroll insisted his show be filmed in Glasgow, the city that has supported his plays.
Other awards went to BBC Scotland's controversial football documentary Rangers – The Men Who Sold The Jerseys, which picked up the honour for Best Current Affairs Programme.
The Best Factual Series Award went to Afghanistan: The Great Game – A Personal View by Rory Stewart, while the Feature Film award was won by Up There, which began life as a short and went on to become an internet hit. Director Zam Salim won Best Director for the same film.
Other winners included: Bad Hotel for Best Game; Afterlife – The Strange Science of Decay for Best Single Documentary; Antiques Road Trip for Best Features/Factual Entertainment; and The Making of Longbird for Best Animation.
Some 500 guests at the ceremony in Glasgow also saw a video tribute from Star Wars director George Lucas for Trisha Biggar, the recipient of the Outstanding Contribution to Craft Award for her costume design on the three Star Wars prequel movies.
Presenters featured the cream of Scots talent, including Kaye Adams, David Hayman, Edith Bowman, Siobhan Redmond and Muriel Gray.
"It was an absolute honour to host the awards and to help celebrate the very best Scottish talent in the film, television and video games industries," said Ms Bowman.
Jude MacLaverty, director of Bafta in Scotland, praised the winners, who she said "reflect the sheer breadth of content being generated in Scotland across film, TV, games and animation".
She added: "It's great to see so much talent celebrated tonight."