
Unforgotten viewers have been left heartbroken by the series finale.
Chris Lang’s drama broadcast the final episode of its fourth run on Monday (30 May), delivering the show’s biggest blow to date.
*Spoilers follow – you have been warned*
Following the dramatic conclusion to the penultimate instalment, which saw Nicola Walker’s DCI Cassie Stuart involved in a car accident, DI Sunny Khan rushed to finish their investigation into the death of Matthew Walsh.
After solving the case, Sunny rushed to the hospital to find out that Cassie succumbed to her injuries with her family being told she would never regain brain activity.
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In devastating scenes, Cassie’s father replays the final voicemail she sent him over and over, in which she promises she will “be better” in the future. Sunny can then be heard eulogising his friend, saying that he “loved” her. As with every series of Unforgotten, the final scene ends in a cemetery – only this time, Sunny stands over Cassie’s grave.
It was all too much for viewers to take.

“What a sad, tragic end to tonight’s #unforgotten,” one person wrote, adding: “Shame we won’t see Nicola Walker as Cassie again.”
Another viewer wrote: “Some character deaths hit hard and that was definitely the case tonight. An incredible four series come to a tragic end. Tonight we all mourn Cassie.”
One fan added that they were in “absolute turmoil over Cassie,” while another stated: “Sunny without Cassie. I can’t. I don’t know how to come to terms with that.”
Following the episode, Bhaskar shared a touching note Walker wrote him while filming what would be her final series.
There is currently no word on whether Unforgotten will return for a fifth series.