Unforgotten is one of the UK's top mystery dramas and will be back for a fifth series, despite star Nicola Walker not returning after her character's dramatic exit last year.
And now creator Chris Lang has revealed that script read-throughs with her replacement, who will be the new partner to DI Sunny Khan played by Sanjeev Bhaskar, have started this week.
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But the identity of Nicola's replacement remains a secret, for now. Chris shared a picture on Twitter of the read-through including part of a profile of the new actress next to Sanjeev, but we can't quite make out who it is.
From just those clues we're taking a punt at Maxine Peake - that's just a guess, though.
On Twitter guesses included Doctor Who's Jodie Whittaker, Cold Feet's Hermione Norris, Sharon Small from The Bay and Inspector Lynley Mysteries and Sandi Toksvig.
In his replies to the Twitter post, Chris says the new detective's identity will be revealed next week - and we can't wait.
Also featured in the image the writer shared is actor Andrew Lancel, who must be playing a new character as he's not featured in any previous series. Andrew is best known for his roles in The Bill and Coronation Street and is himself a huge fan of Unforgotten, tweeting last year: "It’s not often you put a telly programme in your actual diary - 9pm ITV - the last Unforgotten.”
Unforgotten regular, Jordan Long who plays DS Murray Boulting, also appears, as of course does Sanjeev, whose character Sunny will have a new partner after Cassie's tragic death in a car crash in series four.
Last year a spokesperson for the broadcaster said the show would return.
"ITV would like to thank Nicola Walker for playing the brilliant role of Cassie Stuart in four series of Unforgotten which has become one of the best-loved and most critically acclaimed police dramas on TV.
"Nicola and writer Chris Lang decided that Cassie's story would come to an end last night, but that Unforgotten would continue, in series 5, with a new case, and a new 'partner in crime' for DI Sunny Khan."
Unforgotten is a police procedural that covers historical murders and disappearances and has been running since 2015. The fourth series had a record-breaking season posting the show's highest viewing figures.
