Season 20, Episode 02 — Identity Part Two
When Nikki, Jack and Thomas make a horrific discovery in the van, they are confronted with the work of a killer who preys on illegal immigrants. With the help of Clarissa, they must work out where the killer will strike next before more vulnerable people meet the same fate.
Silent Witness originally followed the work of forensic pathologist Dr. Sam Ryan, played by Amanda Burton. In 2004, Burton left the series and Nikki Alexander, played by Emilia Fox, joined Dr. Leo Dalton (William Gaminara) and Dr. Harry Cunningham (Tom Ward) on the forensic pathology team. The series was created by an ex-police officer, Nigel McCrery.