Unforgotten

Despite a tragic turn of events, the team narrows down the suspects. Will they find conclusive proof of who the murder weapon belonged to and succeed in bringing Walsh’s killer to justice?

"That trust and love, that's a real touchstone in Cassie's life." Stars Nicola Walker and Sanjeev Bhaskar reflect on the years of enduring friendship and love between Cassie and Sunny.

Cassie and Sunny interview two of the suspects again and get closer to the truth of what happened to Walsh. Balcombe believes she may have found the cause of death. Unexpectedly, things take a devastating turn for Cassie.

Cassie and Sunny discover Walsh was chased by all four suspects on the night in question. Willets realizes Fiona’s blood sample may have been deliberately lost by Liz. The pathologist identifies a cause of death implying Walsh was murdered.

Nicola Walker walks us through the emotional journey of Cassie Stuart over the years, and the toll it has taken on the hard working DCI.

New crime, new suspects. Meet the murder suspects of Season 4! Liz White, Phaldut Sharma, Andy Nyman, and Susan Lynch introduce their mysterious characters and the threads that tie them all together.

Cassie and Sunny interview the four suspects, who all deny knowing the victim. Boulting discovers Walsh was cautioned three weeks before his death, and Collier manages to locate the rest of Walsh’s body.

Cassie and Sunny identify four potential suspects who trained as police officers together, and two of them are still serving. They have no luck finding the rest of the body and decide to go public about the discovery of Walsh’s remains.

Nicola Walker and Sanjeev Bhaskar describe the gruesome murder at the center of Season 4 and the mystery Cassie and Sunny must unravel.

Sanjeev Bhaskar explains the social media hype about Sunny's iconic backpack, and how it has evolved over the years.

Join series star Sanjeev Bhaskar on a grand tour of the iconic Abbey Road Studios, where the show music is recorded.

The most dramatic season yet begs the question: who exactly is fighting for justice? Season 4 premieres on Sunday, July 11 at 9/8c on MASTERPIECE on PBS.