Following his shock election victory, Tom Dawkins launches an enquiry into the toxicology anomalies at the blast in Scarrow.
As British intelligence locates the whereabouts of al-Qaeda chief Tamin al-Ghamdi, a reluctant Dawkins is pressed to take him out.
Meanwhile, after her superiors at GCHQ fail to take her findings seriously, Agnes reaches out to the one man she thinks could help her.
