Professor T first look sees Jasper behind bars: 'It's weirdly liberating for him'

"He starts to kind of break down really," Ben Miller told RadioTimes.com. "One of the things about Professor T is he's almost got this armour, his personality is almost like an armour to keep people at bay. And it starts to crack and crumble really, and you start to see the person inside a little bit. And that's quite interesting.

"And in other ways he's very resilient. He arrives at a crime scene just after a murder's been committed in the prison and he's completely fearless in pursuing the murderer, with almost no thought for his own safety or any consequences."

Miller added: "So, like all things Professor T, it's a bit of a mix. It's weirdly liberating for him being in the prison because he finally gets to break out of his own prison."

Watch Miller in action below in an exclusive season 3 clip.

Miller also told RadioTimes.com that they filmed inside a real prison, which he described as "a really odd experience".

"They were about to do some renovations, so up until a couple of weeks before we moved in, there were prisoners there," he said. "And after we filmed, the prisoners were going to come back in, so it felt very real."

He continued: "And it's a really odd experience, spending a lot of time in a prison. You feel very moved for what people must go through being in there. It definitely made a difference to the filming. No acting required, really."

Read more:

• Professor T star says fans should "be prepared" for season 3
• Professor T, starring Ben Miller, renewed for season 4

In the drama's latest outing, both Jasper and Christina have "momentous decisions to make".

"Will Christina allow Jasper to incriminate himself to save her career, or will her conscience and the formidable duo of his mother Adelaide (Frances de la Tour) and his therapist Dr Helena (Juliet Stevenson) get the better of her?" reads the official synopsis.

This season will also "reveal what happened the night a young Jasper found his father hanging".

"How involved was his mother Adelaide and what did she really know about her husband's death? With the help of his therapist, Jasper finally manages to piece together his memories of the events despite Adelaide and the Dean's attempts to shield him from the devastating truth."

Professor T season 3 debuts on ITV1 at 9pm on Wednesday 27th March. Check out more of our Drama coverage or visit our TV Guide and Streaming Guide to find out what else is on.

Try Radio Times magazine today and get 10 issues for only £10 – subscribe now. For more from the biggest stars in TV, listen to The Radio Times Podcast.