Downton Abbey star Dan Stevens has said that the wedding of his character Matthew Crawley to Lady Mary could not have come at a better time.

The pair will finally walk up the aisle in the third series of the show, which begins on Sunday night – and Dan admitted that he did not think viewers would have tolerated anymore delays to their marriage.

We would have been hard pushed to stretch the storyline any longer,” Dan said.

“I think we would have been testing the patience of the nation, dare I say the globe, if we had carried on with that.

“But there’s still the issue of will they or won’t they be happy? Will they or won’t they have children, and so on.”

Viewers can also look forward to the first appearance of Hollywood legend Shirley MacLaine in Sunday night’s episode.

Co-star Hugh Bonneville said that the actress’s first meeting with Maggie Smith – who is set for onscreen fireworks with Shirley’s character Martha Levinson – was a memorable one.

“It was extraordinary. Shirley lifted Maggie off the ground and said, ‘My God! My God! Maggie!’,” he said.”