All three parts of the British miniseries based on true events which follows the lead-up to and aftermath of the Novichok poisonings in Salisbury, England in 2018. Police detective Tracy Daszkiewicz (Anne-Marie Duff) attempts to juggle her strained personal life while unravelling what came to be an international incident. The cast also includes Nigel Lindsay, Rafe Spall and Darren Boyd.