Why did Nicola Walker leave Unforgotten? Cassie's fate explained

Cassie was a core part of the Unforgotten series, having appeared since it debuted in 2015.

So, why did Nicola Walker leave the ITV crime drama? Read on to find out more.

Why did Nicola Walker leave Unforgotten?

After being in the role of Cassie for six years, Walker departed the series in the unexpectedly shocking season 4 finale. When the episode aired on 29th March 2021, there was speculation on the cause of her exit. However, speaking to Radio Times magazine, Walker states that just wasn't the case and was actually a joint decision between her and Chris Lang, the creator of Unforgotten.

When speaking about her recent role in BBC One's Marriage, she said: “I’ve worked with [Unforgotten creator] Chris Lang more than any other writer and we are friends. From the very beginning, we talked about Cassie’s story being finite; Chris was always putting her through a story arc that would damage her emotionally. The buzzword was that she was an empath, and the problem with being an empath is that eventually, you break. I felt that to have her keep coming back would make her seem like a superhero. So it was very much a joint and long-planned decision.

“But on reflection – we all feel the same – if we’d known COVID was coming, we would have given people a less depressing storyline. I feel guilty because, when it came out, I thought, ‘Crikey, we could have given them something more cheerful. The last thing they need is to be made to feel really sad about this brilliant cop.’”

She also commented: "I’m not on social media, but when the final episode went out, I almost wanted to join Twitter to tell everyone that I didn’t walk away from the show, nor did they ask me to leave. It was simply that Chris and I thought it was a fantastic, impactful story.

"I love the irony of this brilliant woman dying an accidental death that wouldn’t be investigated in a show about complicated investigations ... We hoped people wouldn't feel we were being cruel by serving up this incredibly sad story."

What happened to Cassie Stewart in Unforgotten?

If you're wondering whether there could be the prospect of a Cassie Stewart return, you'll be sorely disappointed.

Cassie of course met her unlikely demise at the end of season 4 when she was involved in a fatal car accident. She died from brain injuries sustained in the crash and left her team – namely, Sunny – grieving her shock exit.

In this new fifth season, we follow new DCI Jessie as she joins the team and is tasked with investigating the discovery of human remains in a newly-renovated period property in Hammersmith, London. But is this actually a cold case that can be traced back to the 1930s, or could the team be looking at a more recent murder case?

Speaking about Keenan's new character while on set, series showrunner Chris Lang added that Jessie is "in a very different place to Cassie, because Cassie was on something of a descent, both emotionally, but also in terms of her career".

He continued: "She was at an age where she’d done it for 30 years, and she'd had enough. And I always thought that was a really interesting dynamic – to have a hero cop who didn't want to do the job anymore.

"And Jessie is just completely the opposite. She's absolutely at the peak of her powers. I think this is her first job as a DCI, and she's got a lot of energy. And she's very different to Cassie. The relationship between her and Sunny will be very different."

Read more:

• Unforgotten trailer: "I don't intend to run this team like she did"
• Unforgotten’s Sanjeev Bhaskar teases “unique” mystery for season 5
• Unforgotten creator already has plans for season 6

Unforgotten season 5 will air on ITV1 and ITVX on Monday 27th February 2023, and all four previous seasons are currently available to stream on ITVX.

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