The multi-award winning drama, Silent Witness, returns for Series 21 in 2018. Dr Nikki Alexander (Emilia Fox), Jack Hodgson (David Caves), Dr Thomas Chamberlain (Richard Lintern) and Clarissa Mullery (Liz Carr) form a committed team of forensic pathologists and scientists, trying to figure out how and why the victim died.

Nikki and Jack are affected from the fallout after Mexico, while there's a cuckoo in the nest. A series of tragic events are linked to a cyber hacking. A US Diplomat is shot dead in Central London. Care home abuse is uncovered after a road traffic accident. Festive celebrations are interrupted by the aftermath of a shooting spree at a family house.