Mark Gatiss films ‘Who Do You Think You Are?’ in Derry

Writer and actor Mark Gatiss pictured in Derry's Guildhall with its distinctive stained glass windows behind him.
Writer and actor Mark Gatiss pictured in Derry's Guildhall with its distinctive stained glass windows behind him.

Writer and actor Mark Gatiss, star of TV’s ‘Sherlock’ and ‘Game of Thrones’, has been in Derry to uncover his Irish roots as part of the BBC’s popular ‘Who Do You Think You Are?’ series.

The mult-italented 48­-year­-old (pictured right while in Derry),­ who has also written episodes of the revamped ‘Doctor Who’ series on BBC1, ­dropped into the city’s Guildhall to find out more about his mother’s side of the family.

His late mum’s maiden name, O’Kane, is a popular name in both Derry City and the surrounding county.

It’s understood he also follows the trail of his great­, great­ grandfather who owned a lot of land in Co Derry.

It’s during this investigation of his family tree that he drops into the Guildhall to view land ownership records to discover just exactly where this land came from.

During his research, he also discovers that he has a connection with the name O’Mullen.

The ‘Journal’ understands that ‘The League of Gentleman’ star ­- who co­-created the award-winning ‘Sherlock’ TV series which stars Benedict Cumberbach and Martin Freeman - paid a hush-hush visit to Derry back in February to film the Irish section of the TV show in which celebrities trace their family trees.

Writing on Twitter at that time, he somewhat cryptically said: “I’ve had such an amazing time in ‘Derry. Sad to be leaving but I will return!”

Horror films and ghost stories have always been Mark Gatiss’ obsession and he has always wondered whether this love of the ghastly and ghoulish springs from Irish ancestry on his mother’s side.

“The big mystical thing for me is my mother’s side,” he says. “The Irishness of her side of the family always appealed to me. I’ve never really delved very deeply.”

“I used to walk around the football pitch talking about horror films with my best friend. History has also always been one of my biggest passions. It’s a sort of affinity with it all in a way. My mum used to say I had an old soul, which I always liked.”

It’s understood that, as part of his ‘Who Do You Think You Are?’ research, Mark investigates the O’Kane clan link to a famous Co Derry vampire legend ­- something that is, of course, right up his

Derry’s connection with the vampire legend centres around the legend of Abhartach, a magical dwarf from south of the county, who rose from the dead, demanding blood from terrified

Abhartach was a tyrant who terrorised the people of south Derry until he was killed by a local chieftain, possibly named Cathrain - believed to be a corruption of O Cathain or O’Kane: Mark Gatiss’ mum’s surname before she married.

Mark also finds his O’Mullen connection, particularly that of George O’Mullen, intriguing.

“George O’Mullan was a brilliant storyteller,” he says. “I don’t want to over ­romanticise it, but it sort of feels like, maybe, that’s where I get it from. Somehow there’s a little slant towards all that which comes from being of this stock going way, way, way back.”

n ‘Who Do You Think You Are?’ featuring Mark Gatiss is to be broadcast on BBC 1 in October.