Unforgotten is a slow-burning crime drama about people who cannot let go. Created by Chris Lang, the series follows London detectives Cassie Stuart and Sunny Khan as they reopen cold cases decades after the crimes were committed. It airs on ITV and runs six episodes per season, with a new case each year.
Trailer, via ITV.
The Case Files
The show opens with the murder of Jimmy Sullivan, a 17-year-old who disappeared in 1976. His remains are found during demolition work in north London. Season 2 brings David Walker, a Conservative Party consultant whose saponified remains appear in a suitcase in the River Lea. Season 3 centers on Hayley Reid, a schoolgirl who vanished on New Year’s Eve 1999, whose skeleton turns up on the M1 motorway. Season 4 finds Matthew Walsh’s headless, handless corpse inside an old freezer, frozen since his disappearance.
Each case introduces characters whose lives cross the victim’s in ways that take episodes to reveal.
Cassie’s Struggle
Nicola Walker plays Cassie Stuart with a controlled fury. Cassie talks openly about why she works these cases. She wants to find the truth, offer closure, and catch the criminal. But her inner motive is darker. She says solving a case helps her move on, adding:
“If we can do this right, if we can ignore who they are and do it by the book, then all the questions [and faces] might all go away. And I might be able to sleep at night.”
That tension defines the series. Cassie’s family life — her father, her son, her strained friendships — all circle back to the pressure of her job.
Jessie Takes Over
Season 5 changed the lead. Sinéad Keenan replaces Nicola Walker as DCI Jessie James, becoming Sunny’s new partner. Keenan brings a quieter, more measured presence, and the show carries forward without losing its momentum.
The cases keep coming, each one as grim as the last. The show explores how grief lasts across generations, and how the dead leave traces on the living.
The Awards
Unforgotten has earned strong reviews. Tom Courtenay won the 2016 BAFTA TV Award for Best Supporting Actor for the first series. Mark Bonnar won the 2017 BAFTA Scotland for Best Actor in Television for the second series.
| Season | Lead | Case |
|---|---|---|
| 1 | Cassie Stuart | Jimmy Sullivan |
| 2 | Cassie Stuart | David Walker |
| 3 | Cassie Stuart | Hayley Reid |
| 4 | Cassie Stuart | Matthew Walsh |
| 5 | Jessie James | Precious Fala |
The Formula
The writing is patient. The show trusts the audience to sit with uncertainty. It does not rush answers, and that restraint pays off.
Some cases feel more compelling than others, and the formula — a buried body, a hidden connection, a final twist — repeats without much variation across six seasons.
Unforgotten is best when it slows down. Its strengths are Cassie’s internal conflict and the methodical work of its detectives. The show rewards patience and delivers a payoff that feels earned.
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