BBC's Mum star Peter Mullan promises final series 'finishes as it should'

Viewers have been enchanted by the gentle humour in Mum.

And Mum actor Peter Mullan says that the final series of the heart-warming BBC2 comedy will end in the right way.

Over three series millions of fans have been captivated by the love story between Michael (Mullan) and Cathy (Lesley Manville).

And, as the sitcom continues its last series tonight, Peter, 59, says it will come to a ‘natural’ conclusion.

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“It finishes as it should,” he told TV Times. “The ending feels very natural – it doesn’t feel forced with everyone having a happy moment.”

Peter added that he was thrown by the revelation that Cathy and Michael had already slept together.

‘The bravest thing the writer Stefan Golaszewski has done this series was showing that Cathy and Michael have already been to bed together, so he got rid of the “will they, won’t they” element. When I read that in the first episode, I thought I’d read the scripts in the wrong order. I didn’t expect it.'

The romance between the pair has certainly been a slow burner and over the series Peter, who was nominated for a BAFTA for his performance, has had fans rooting for them to become a couple.

"Folks always come up and say, 'Aww!' It’s quite soppy and they have been lovely to play. Having two central characters being grounded within this place of madness means it’s very real.”

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With Mum coming to an end soon, Peter says he will ‘deeply’ miss working with Lesley.

“She’s a genius, as are the rest of the cast. It was one of those rare occasions when we were all one big happy family.”

Mum continues with episode three on BBC2 this evening at 10.00pm. All three series of Mum are available as box sets on BBCiPlayer.