Rufus Sewell on Lord M's "changed relationship" with Jenna Coleman's Queen in Victoria series two

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Victoria's beloved former PM will make an appearance in Sunday night's episode, reuniting with Jenna Coleman's Queen Victoria and Tom Hughes' Prince Albert.

"By the time Albert arrived Melbourne's role and the nature of his relationship with Victoria had changed, as it should," Sewell continues.

"After that Melbourne, who had always been a very vital man, changed and ageing caught up with him relatively quickly so what was interesting was navigating his changed relationship with Victoria and also with Albert.

"There had been a certain level of imagined antagonism to start off with, but actually in reality they liked each rather a lot once the original suspicion went away, so it was lovely to come back to work a little more with Tom Hughes."

Lord M resigned as Prime Minister for the final time in August 1841, and while Victoria continued to write letters to him for a short period after he left public office, Sewell initially expected not to appear in the second series of Daisy Goodwin's historical drama.

“One of the things that appealed about the role originally was that it was finite; a lovely contained story with a beginning middle and end," he explains. "I really didn't want Melbourne to be hanging around beyond the natural span of his story.

"All the same, I knew that if all went well, I’d probably regret leaving when it came to it and it turned out I was right.

"When the producers came to me with a way to bring him back in season two that was still true to the story, I was only too happy to come back."