Warning: This article contains spoilers about the ending of Unforgotten series four which some readers may prefer to avoid.
Unforgotten creator Chris Lang has revealed that he is already working on the show's fifth series.
The fourth series - broadcast on ITV earlier this year - ended with the shock confirmation that lead character Cassie Stewart (Nicola Walker) had died in a car crash.
ITV was quick to announce that the show would live on, however, with a new lead being brought in to work alongside Sunny Khan (Sanjeev Bhaskar) and the rest of the team.
Speaking to Radio Times, Lang confirmed that Cassie's replacement will be female and will be a completely new character to viewers.
"So I've kind of got a rough idea, obviously, who she is," he said. "It's an evolutionary process when you write both the series and the characters and they evolve over the course of the writing process, six months or so.
"So I have a pretty good idea who she was and who she is and what her story is. And yes, it's a woman. But it will keep evolving until the day we deliver it because you still rewrite in the edit."
Lang also opened up on Walker's decision to quit the show, adding: "It was decided between me and Nicola, really. It was a discussion that we had together over a couple of series. In fact, we certainly discussed it when we were making series three.
"So it was just a mutual decision that her story would probably come to an end by the end of series four."
The most recent series was a huge ratings hit for ITV, with the final episode consolidating to 9.5 million viewers.