Professor T's Ben Miller reacts to double finale twist: "It's really, really sad"

There were two huge moments, the first being Jasper's discovery about the death of his father.

The professor (Ben Miller) had always believed that his dad had killed himself, but in a dramatic turn it emerged that his mother Adelaide (Frances de la Tour) had hit him over the head to protect her son during one of her husband's drunken outbursts.

Speaking exclusively to RadioTimes.com about the reveal, Miller said: "It's huge. It's seismic because he realises that his mother made a huge sacrifice for him and that he's completely got her wrong, really.

"I think children do sort of have to put the blame somewhere and often they put the blame on the nearest parental figure. But he's suddenly realised that all the resentment he's had against his mother is completely unfounded and he's had a completely false impression of what her motives are."

Miller went on to discuss how his character has evolved over the course of three seasons in light of what he now knows about his mother.

"I think when you're trying to bring about big psychic change within yourself, often the first steps feel quite easy," he said. "To step through the door is quite easy, what's harder is to stay there where it's uncomfortable, where you're defenceless.

"The first season, clearly something deep within him really, really wants to get to the truth. That's the reason for moving back into the abandoned house that they have in Cambridge.

"And it's partly his reason for getting involved with the police again, because it's bringing him into reality, and the whole show is about somebody who's hermetically sealed from reality trying to break out of their prison and join humanity. So it's a massive journey.

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"And he's made huge progress. By the end of this third season, he understands, painful as it is, a bit more about his own childhood. He has a way of understanding the trauma he went through as a child."

The finale also delivered another intensely sad moment: the death of DS Lisa Donckers (Emma Naomi), who was struck by a car while on duty.

In season 3, she was newly promoted and her relationship with Winter was as solid as it had ever been, which prompted him to propose to her. But tragically, their time together was cut abruptly and brutally short.

"It's an assault on the emotions," said White, while Miller described the development as "really, really sad".

"He's on the brink of huge change, where he's climbed all the ladders, and then one huge snake takes him right back to the beginning," he added.

"It's a huge setback, so the struggle continues."

A fourth season of Professor T has been confirmed, with Miller and White joined once again by de la Tour, Juliet Stevenson (Dr Helena Goldberg) and Sunetra Sarker (DI Maiya Goswami).

The action will pick up six months after the events of Lisa's death as the police turn their attention to a "dangerous crime wave", according to Variety.

Elsewhere, the "gloves are well and truly off" for our leading man in his lectures, and he also explores a "new musical pursuit".

Romance is also on the cards for Adelaide, the "lines between professional and personal become blurred" for Helena, and Winter becomes Maiya's right-hand man.

Professor T seasons 1-3 are available to stream now on ITVX.

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