Unforgotten returns this week with DCI Cassie Stuart at a crossroads – but why does Cassie want to retire?
What happened to her at the end of series three, and why is she on sick leave?
Here’s everything you need to know to get you up to speed.
***Warning: may contain spoilers from series three and four ahead***
Read more: Unforgotten series 4: Fans can’t wait as trailer released by ITV
What happened to Cassie at the end of series three?
Doctor Finch admits he’s a rapist and serial killer whose crimes went well beyond one or two victims.
Buried around the country are the remains of untold numbers of adolescent girls who he raped and killed over many decades.
A psychopath, he expresses no guilt about his crimes.
His unnerving lack of remorse causes Cassie to crack under the emotional weight of her career dealing with grisly crimes.
The Finch case was especially distressing for Cassie because she had accidentally left a confidential file in a café.
A member of the public found it and used it to out the man as a murder suspect online, after which a vigilante stabbed him to death in the street.
After taking Finch’s confession, Cassie took three months of sick leave to help her cope with her trauma.
Writer Chris Lang explains: “In this, I wanted to write about murder that is about evil, really.
“Because it felt very different, and it’s much harder to understand, which was what those scenes were all about – listening to someone talking extremely dispassionately about the most heinous crimes.”
Why is Cassie on sick leave?
DCI Cassie Stuart takes sick leave at the end of series three.
Cassie’s mental health has suffered after spending almost 30 years as a detective investigating the most brutal murder cases.
Actress Nicola Walker, who plays Cassie, says: “Having gone through what she went through in the last storyline, she knows that she is broken, that she should stop.
“But also, on a practical level, she literally cannot leave the police force without that settlement and why should she?
“Her problem has always been that she gets too personally involved…
“But how could you not get personally involved in the things she deals with?”
Read more: Unforgotten series four: ITV drama returns in February with guest stars including Sheila Hancock
Why does Cassie want to retire? Series catch up
When Unforgotten series four begins, DCI Cassie Stuart has been away from work for a year.
She’s living with boyfriend John and her 21-year-old son Adam.
Doctors have diagnosed her dad Martin with rapid-onset dementia.
Now, just months away from receiving her police pension, she’s requesting medical retirement and feeling unable to cope with a return to work.
She says: “I know, unequivocally, that I don’t want to go back. I’ve already given the job everything I have.”
But it’s not that simple, as she’s just three months away from having served 30 years.
Why does Cassie want to retire? Actress Nicola Walker reveals all
Actress Nicola Walker explains: “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.
“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.”
Unforgotten series four episode one
As Nicola battles with the police authorities about a return to work, her colleague DS Sunny Khan (Sanjeev Bhaskar) is still working the cold case unit.
The headless, handless body of a man is found in a scrapyard, and Sunny must find clues as to his identity.
He’s been stored in a domestic freezer, possibly for 30 years.
But who is he? And will Cassie return to help solve the case?
Unforgotten series four kicks off on Monday February 22 2021 at 9pm on ITV1.
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