Expert British hostage negotiator Dominic King is called upon when a businesswoman from the UK is kidnapped in South Africa by a sinister figure named Willard.

A new kidnapping each season, the story focusing on the kidnappers and the people affected.

The series follows two women—modern-day archeologist Alice Tanner (Vanessa Kirby) and Alaïs Pelletier du Mas (Jessica Brown Findlay) who lives through the Crusades and Cathar massacres in medieval France—and their quest to find the Holy Grail.

An anti-terrorist organization fakes the death of a jailed, convicted murderer and trains her in the fighting skills necessary to succeed in her new job.