Yes, that's right, foul-mouthed matriarch Agnes Brown is calling in the assistance of Lord Grantham.
Brendan O'Carroll (57) has said he wants to sign top toff actor Bonneville for a role in his upcoming movie Mrs Brown: De Filum.
Based on the smash-hit series, the €4.5m film will see Agnes Brown take on a syndicate wanting to build a shopping centre where her vegetable stall is.
And O'Carroll wants Bonneville to play the part of a stammering lawyer who suffers from Tourette's Syndrome. He will defend Agnes in court and will give her a run for her money when it comes to cursing on set.
His character hasn't made the best impression on the legal world and has rarely practised at the bar.
"This barrister hasn't represented anyone for five years," comedian Brendan explains.
"Because when he is under pressure he develops Tourettes. I'm hoping to get Hugh Bonneville for the part."
O'Carroll says he wrote the part with Bonneville in mind and hopes he will agree to join the cast of Mrs Brown's Boys.
"I wrote it with him in mind and couldn't stop laughing -- I think he'd be brilliant," he said.
"The movie will revolve around a court case after a politician, developer and a banker team up to close a Dublin market.
"They think Agnes's stall will be easy to shut down because she's a widow -- but she has no intention of going anywhere without a fight."
But the authorities don't realise that Agnes is a force to be reckoned with and she turns to her daughter Cathy, played by Brendan's wife Jennifer Gibney, for advice.
"She employs a solicitor, who her daughter Cathy falls for, and a barrister -- which is where Hugh comes in."
The film is due to start shooting this August with a 2014 release date. Last week, the BAFTA-winning series picked up the National Television Award for Best Sitcom.
Bonneville has gained a reputation for playing upper-crust gents and a role in Mrs Brown: De Filum as a cursing and socially inept lawyer would see him take on a very different role.