The man behind some of the worst terrorist attacks on the west escapes during a prison break masterminded by his British wife, and Col Adeena Donovan needs the situation cleared up quickly and decides to reinstate the disbanded Section 20. The all-new members of the unit set out on a life-or-death mission that will take them across the Middle East and Europe, and plunge them into the paths of Saudi princes and Russian FSB agents.
Section 20 start to close in on terrorist Omair Idrisi and his wife Jane Lowry, but the team is forced to extract devious arms dealer Morgan Ives from Libya.
As Jane Lowry surfaces in Budapest, Mac and Wyatt are forced to go undercover to infiltrate a dangerous group of white supremacists that has something she needs.
Things aren't looking good for Mac. He's blown his cover and is now facing certain death. Donovan digs into Zarin's past... and she doesn't like what she learns.
Section 20 must stop Lowry and Dr Markov from making and unleashing a deadly chemical weapon. In desperate need of intel, Novin infiltrates a drug lord's home.
Lowry calls on a young jihadi to unleash the deadly gas in a busy airport, while Reynolds is forced to make a life-defining decision as Section 20 races to prevent the attack.
Section 20 attempts to track down ex-CIA contractor Rachel Sheridan, who knows the location of the black site where they think Omair Idrisi is being held.
Jensen starts to delve into Project Tenebrae, while Mac and Wyatt head to the black site where Idrisi is imprisoned to break him out before Lowry gets to him.
The team run into trouble as they race to get Idrisi back across Europe. The surprises keep coming as they learn the truth about Jensen and Project Tenebrae.
Section 20 are desperate to clear their names. And to do so, they hatch a big and wreckless plan.