BAFTA nominated actors Nicola Walker and Sanjeev Bhaskar reprise their roles as DCI Cassie Stuart and DI Sunny Khan as production begins on the highly-anticipated fourth series of critically acclaimed drama, Unforgotten.

Produced by independent production company Mainstreet Pictures in partnership with Masterpiece, and devised and written by acclaimed screenwriter Chris Lang (Innocent, Dark Heart), the new six-part series charts a fresh investigation into another emotionally-charged cold case murder. 

The fourth series opens with the discovery of a dismembered body in a scrap metal yard, which the team believe has been stored in a domestic freezer for thirty years. A unique Millwall Football Club tattoo leads to the victim being identified as Matthew Walsh, a young man in his mid-twenties who went missing in March 1990.

The team quickly track the purchase of the freezer to Robert Fogerty, but they are disappointed to learn he’s recently died a lonely, broken man. On looking further into his past, they discover a drink driving conviction on the same night their victim, Matthew Walsh, went missing, and intriguingly there were four passengers in the car with him at the time.

The main cast will be joined by Sheila Hancock (New Tricks, Delicious), Susan Lynch (Killing Eve, Apple Tree Yard), Phaldut Sharma (Hanna, EastEnders), Liz White (Life On Mars, Ackley Bridge), Andy Nyman (Wanderlust, Peaky Blinders), Clare Calbraith (Baptiste, Little Boy Blue) and Lucy Speed (Marcella, National Treasure), along with returning actors Peter Egan (Downton Abbey, Hold The Sunset), Alastair Mackenzie (Deep Water, Cold Feet), Carolina Main (Blood, Grantchester), Lewis Reeves (Uncle, Inspector George Gently) and Jordan Long (Prime Suspect 1973, SS-GB).