UNFORGOTTEN, Season 3– NEW SERIES (NR) When human remains are found by a highway near London, Cassie (Nicola Walker) and Sunny (Sanjeev Bhaskar) is called in. Dogged work leads the team to a sixteen-year-old girl who went missing on the eve of the millennium. A close-knit group of old school friends holds the key to what happened. Is one of them capable of murder? Cassie is determined to correct the mistakes made in the original investigation no matter the personal cost.