Professor T's Ben Miller: 'Jasper starts to crack up in prison!'

"He actually ends up going to prison in season three for quite a long time! What starts initially as discharging a firearm soon becomes attempted murder, and he's then facing really quite a substantial sentence, so things get really serious. And of course prison is the worst place for him, because he likes his creature comforts, he likes his very orderly world in his ivory tower, and to be ripped out of that and thrown into a cell that he's got to share with another human being — it's not his favourite thing! Shocking hygiene, terrible food, it's a real struggle — except of course for the silver lining that he's fascinated by the criminals that he finds himself surrounded by. He's pulled in two directions at once: wanting to get out of there as fast as he possibly can, but also wanting to make the most of the opportunity to observe the criminal mind at close hand!"

"His therapist [Dr Helena Goldberg, played by Juliet Stevenson] is permitted to visit him in prison. Their therapy really starts to take off because he starts to crack up in the prison, and that makes him vulnerable, which makes him able to be more honest in his therapy sessions, and he really starts to make some progress. The mystery of Professor T has always been about what happened with his father — we've seen these fractured memories of him seeing his father hanging when he was a boy, and others have involved him with a shotgun to his father's chest — in this season, we do find out exactly what happened to his father the night he was murdered, and obviously that then has huge implications for season four."

"Their relationship gets worse in this series! In fact, he won't let Adelaide [played by Frances de la Tour] visit him in prison, and that becomes very difficult for her and for him. Their relationship deteriorates further and further throughout these six stories, it's quite sad. But as he begins to acknowledge his trauma in his therapy, he starts to blame his mother more and more. I love acting with Frances and Juliet, it was so much really juicy stuff."

"Well, she and the Professor don't get on! She works from the gut, and she's a real people person — she can't see what on earth the police have been doing, having some cranky academic professor helping them with cases. She's like 'no, this guy is out, this is not happening, this is totally against procedure!' So they really get off on the wrong foot, and it's interesting because that brings out a new side of Professor T — for the first time we see him wanting to prove himself to somebody and earn respect. He doesn't just have to fight for his position there, but also in the faculty of criminology, because of course other people have moved in on his patch. No one hangs around in academia!"

"I know, it's very exciting! And one of the nice things for me is that I think we start filming in the second week of April, so season three will be going out at the same time. We'll really be able to immerse ourselves in this world while we're doing it!"