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Unforgotten Season 4 on Masterpiece

6-Parts Airing Sundays at 9:00 p.m. Beginning July 11


Official Teaser

The most dramatic season yet begs the question: who exactly is fighting for justice?

In the series' most dramatic season, Cassie and Sunny investigate a cold case with alarming links to the police force. Can the force ever really be trusted, and will Cassie and Sunny find themselves on the wrong side of the law?


UNFORGOTTEN Season 4 : Episode One

Premieres Sunday, July 11, 2021, 9:00 - 10:00 p.m. 

Parts of a body are found. The team believes the remains have been stored for a long time. After deciding to retire, Cassie learns she must complete 30 years of service to receive her pension.


UNFORGOTTEN Season 4 : Episode Two

Premieres Sunday, July 18, 2021, 9:00 - 10:00 p.m. 

Cassie and Sunny identify four potential suspects who trained as police officers. They have no luck finding the rest of the body and decide to go public with the discovery of Walsh’s remains.

UNFORGOTTEN Season 4 : Episode Three

Premieres Sunday, July 25, 2021, 9:00 - 10:00 p.m.

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

UNFORGOTTEN Season 4 : Episode Four

Premieres Sunday, August 1, 2021, 9:00 - 10:00 p.m. 

Cassie and Sunny discover Walsh was chased by all four suspects on the night in question. The pathologist identifies a cause of death implying Walsh was murdered.

UNFORGOTTEN Season 4 : Episode Five

Premieres Sunday, August 8, 2021, 9:00 - 10:00 p.m. 

Cassie and Sunny interview two of the suspects again and get closer to the truth. Balcombe believes she knows the cause of Walsh’s death. Things take an unexpected and devastating turn for Cassie.


UNFORGOTTEN Season 4 : Episode Six

Premieres Sunday, August 15, 2021, 9:00 - 10:00 p.m. 

Despite a tragic turn of events, Sunny and the team narrow down the suspects. Will they succeed in bringing Walsh’s killer to justice?