Chris Tarrant's grandson mistook Michael Sheen for his grandad while watching 'Quiz'.

Chris Tarrant

Chris Tarrant

The 51-year-old actor portrayed the former 'Who Wants To Be A Millionaire?' host in the ITV series - which told the true story of Major Charles Ingram and his wife Diana cheating on the quiz show - and his resemblance left Chris' four-year-old grandson Harris confused when he saw the familiar face.

Chris' daughter Fia Tarrant shared a clip of her son watching the show on Tuesday (21.04.20), and she added the caption: "Monster has never seen his grandpa on TV before so I thought I'd see what his reaction would be seeing @michaelsheen."

In the clip, Harris is seen watching Michael play Chris, and Fia asks: "Who is that?"

He responds: "Grandpa!"

Fia corrects her son, saying: "That's not grandpa, I promise you," but he is adamant he is watching his grandad on the television.

The clip was later shared by Michael on Twitter, and the star claimed it was the "best review I ever had".

Michael has previously revealed he doesn't like to meet the characters he portrays in real life, but ended up bumping into Chris after filming the drama series.

He recalled: "Just coincidentally, I bumped into him at the Pride of Britain Awards. I was having a photograph taken, and I heard a voice going, 'You don't look anything like me.' And there was Chris Tarrant."

But since the show screened, Michael would love the chance to host the game show - which is currently presented by Jeremy Clarkson - in character.

He said: "To do it on 'Who Wants to Be A Millionaire?' for 'Quiz' and getting to be the person who is so brilliant at doing it as well, I loved that.

"I'd like to take part as a contestant but I would also like to host it. Not as me, as Chris Tarrant.

"I'm the sort of person who, when you play board games with the family, I like to be the question-asker, the person in charge. I love that."