Beautiful Boy is the true life story of Nic Sheff and his battle with substance abuse.
The Queen guitarist and Bohemian Rhapsody movie exec producer has posted a video of him giving his on-screen alter ego, Gwilym Lee, an impromptu demonstration on the old six-string.
Apparently the footage came from Bryan Singer, who initially produced the film before being fired and replaced by Jim Beach.
"When the BR team were shooting this scene," wrote Brian, "I happened to be around, so Gwil invited me to have a go! How did I do, folks?"
We think he's fishing for compliments there, so we'd say: "8/10 - keep working on your scales".
The film, which recently picked up two Golden Globe gongs, is likely to be in the running for an Oscar or two when the nominations are revealed next week.
Some of the stars of the new Mary Queen of Scots film attend its Scottish premiere in Edinburgh.
M. Night Shyamalan's latest film Glass has just been released in cinemas, it is the sequel to the 2000 film Unbreakable starring Bruce Willis.