Turns out we have a bona fide Hollywood A-lister walking the streets of Dublin at the moment, as Mel Gibson has arrived here to begin filming his upcoming movie The Professor and the Madman, and will soon be joined by his co-star Sean Penn.

The Oscar-winning director has been spotted in FX Buckley Steakhouse on Pembroke Street and appears to be staying in the Shelbourne.

The Professor and the Madman will be shot in Dublin over the next eight weeks and is based on the 1998 best-selling novel The Surgeon of Crowthorne, which Gibson has had the rights to for almost twenty years now.

It tells the story of the making of the Oxford English Dictionary by editor Sir James Murray (Gibson) and one of his most prolific contributors, the eccentric Dr. W. C. Minor, who was imprisoned in a lunatic asylum at the time.

The film has been co-funded by the Irish Film Board, while there's also an Irish supporting cast including Rob McCormack, Abigail Coburn and Zoe Moran.

It wouldn't be the first time Mel Gibson brought one of his movies to Ireland, as he famously shot his Oscar-winning flick Braveheart here back in 1996. No doubt he feels very at home here though considering his mother was from Longford, and he was actually named after the Cathedral here. (You've probably heard that 'fun fact' about a dozen times, but just in case).

Gibson's career and personal life appeared to go somewhat off the rails in recent years, but looks like the 60-year-old is starting to get things back on track, with his film Hacksaw Bridge, starring Andrew Garfield, garnering positive reviews at the Venice Film Festival, while his next film, Blood Father, is out in Irish cinemas on October 7th.

He's also expecting his ninth (yes, NINTH) child with his girlfriend, writer Rosalind Ross, so looks like everything's coming up Mel Gibson.