Unforgotten series 4: ITV's cold-case thriller returns to screens in February

The popular crime drama starring Nicola Walker and Sanjeev Bhaskar is back on our screens with new cast members and another decades-old mystery to solve.

By Katie Archer Published: 22 February 2021 - 4.42pm
ITV Nicola Walker and Sanjeev Bhaskar in Unforgotten

Fans of hit crime drama Unforgotten will be thrilled to hear that a new cold case for detectives Cassie Stuart and Sunil 'Sunny' Khan (played by Nicola Walker and Sanjeev Bhaskar) will hit our screens in 2021.

Here’s all you need to know about the forthcoming series 4 of Unforgotten.

When is Unforgotten series 4 on TV?

Unforgotten will be back on our screens at 9pm on Monday, February 22, 2021.

The new episodes began filming in January 2020, however production had to be suspended in March as a result of the lockdown prompted by the COVID-19 pandemic.

The cast eventually returned to the set in September, the show's official Twitter account confirming the resumption of filming by sharing a picture of a clapperboard from the production. 

Nicola Walker said the break in filming actually helped create the right atmosphere to bring back DCI Cassie Stuart.

"I am sure everyone feels this… you come back to a job and you think ‘I don’t know if I can still do this.’ It is a really strange feeling," she explained.

"And ironically that was fine for me because that is exactly where Cassie is this year, which struck me as rather funny. It was perfect for Cassie because she doesn’t know if she can do it anymore and on a very real level I wasn’t sure that I could either. So it worked in my favour rather than against me.”

Sanjeev Bhaskar revealed that the cast and crew had to stick to strict Covid-19 regulations when filming resumed.

"It was incredibly reassuring, with us being tested and then put into mini-bubbles," he said.

"You had to have your temperature checked before you came onto set, the set was marked out in zones and only certain people could be in certain zones, so it was all very comforting.

"Once you got into the scenes it felt like it did before but it was very strange to begin with. Also, actors are very tactile so it was weird not to be able to shake hands or hug anyone, that was probably the biggest challenge. It was strange, but it was lovely to be back.

"Everyone was responsible when it came to following the rules. It doesn’t need to be terrible and we all knew why we were doing it. Within that as well people have different family setups, some people are looking after vulnerable people and some have kids so it was a good, clear set of rules and that was reassuring. We felt very lucky we got to go back at all – we all counted our blessings.”

Who is in the cast?

Sheila Hancock ITV

Nicola Walker (Last Tango in Halifax, The Split) returns as DCI Cassie Stuart, alongside Sanjeev Bhaskar (Yesterday, Goodness Gracious Me) as DI Sunny Khan.

Other returning actors include Peter Egan (Downton Abbey), Alastair Mackenzie (Deep Water), Carolina Main (Blood), Lewis Reeves (Uncle) and Jordan Long (Prime Suspect 1973).

Also featuring in the cast will be Sheila Hancock (New Tricks), Susan Lynch (Killing Eve), Phaldut Sharma (Hanna), Liz White (Life on Mars), Andy Nyman (Wanderlust), Clare Calbraith (Baptiste) and Lucy Speed (EastEnders).

Unforgotten series 4: Meet the cast and characters

What will happen in series 4?

As ever, we’ll see some seriously creepy cold cases resurface for the new episodes.

In the series' opening episode, the team discovers a dismembered body in a scrap metal yard that appears to have been stored in a domestic freezer for 30 years.

Helped by a distinctive Millwall Football Club tattoo, they’re able to identify the victim as a young man who went missing in 1990.

Sanjeev Bhaskar and Nicola Walker ITV

While it doesn’t take long to trace the owner of the freezer, the detectives soon discover that he recently died a lonely, isolated man, and had a drink-driving conviction for the same night the victim went missing.

Intriguingly, it turns out that there were four other passengers in the car that night. Over the course of the series we meet the quartet - Ram Sidhu and his wife Anna who are expecting their first baby together in London; Liz Baildon and her fiancée Janet who live in Cambridge; Fiona Grayson, her partner Geoff and their children in the Peak District; and Dean Barton and his wife Marnie who live in Rochester with their disabled son, Jack, and his younger sibling, Casper. 

All in their late forties, their lives are looking good, until the mystery of the body comes back to haunt them and threatens to destroy everything they’ve built for themselves over the last 30 years.

Susan Lynch ITV

Meanwhile, Cassie has her own problems to deal with – she’d decided to retire from the police force, but when she discovers that she will not get her full pension without completing her 30 years’ service, she is forced to return to work.

It’s bad news for her, but good news for viewers who will be looking forward to seeing more of her partnership with Sunny.

Nicola Walker said: “When we left Cassie at the end of the last series she felt it necessary to stop, she definitely had what would have been loosely termed ‘a breakdown’ and we were left wondering if she was going to come back.

"When we meet her this series you realise she doesn’t really want to come back but she is in a terrible position that she will lose a massive amount of her pension pay out on a technicality if she doesn’t come back and complete a certain number of months to comply with her pension.

“It is awful, she is in a complete trap so she agrees to come back so she can access the full amount of her pension because her dad is getting more and more ill and she is looking at the fact that she will probably be financially responsible for her father’s care.

"So she is completely caught. Her entire career she has very dedicatedly given to the police force. She is angry and feels very betrayed and that’s how she goes into this series’ story."

Writer Chris Lang commented: “I am so excited to be bringing back the Unforgotten team for a fourth series, as Cassie and Sunny take on perhaps their most challenging case to date. Once again, we have assembled an astonishing cast.

"Unforgotten 4 will once again explore the fallout from and the investigation in to, an historic murder case, but the primary theme of this series, will be society’s relationship with the police. 

"The investigation will show the best of the police and the worst, and at a time of unprecedented cutbacks, it will ask a number of difficult questions about the police force as an institution. It will ask what do we expect them to be? It will ask if that is compatible with what they are capable of being? It will ask how much we now take for granted the fact that on a daily basis, these men and women walk towards danger. And, after decades of bruising revelations about their probity, it will ask if we can ever again truly trust them."

Unforgotten series 4 trailer

You can watch the new Unforgotten trailer below:

Episode 3 of Unforgotten airs on ITV and ITV Hub at 9pm on Tuesday, March 9. The remaining episodes 4-6 will then be back to Monday nights at 9pm from March 15.

Catch up with season 4 so far on ITV Hub.

Watch seasons 1-3 of Unforgotten on BritBox.

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