David Oyelowo plays an MI5 officer who travels to Egypt to question a young man he believes is planning a terrorist attack using ricin.
Ahmed manages to elude them, and Ekubo suggests he may be heading to Cairo to meet with a contact who can assist with manufacturing ricin.
Shortly afterwards, he hears that Ahmed has been arrested by Egyptian police along with several other men at a farm growing castor oil plants, the seeds of which can be used to make ricin.
Frustrated with the slow progress, Ekubo asks a colleague to find out the name of the interrogating officer from Egypt's State Security Investigations Service—a Colonel Hazem Ashraf (Makram Khoury).
Ekubo returns to London, and is called into the office of the head of Section G. She tells him that his meeting at the coffeehouse with Hazem has been photographed by an activist blogger in Egypt who is investigating the colonel, and the story is about to go public.
With his career in the service essentially over, Ekubo watches as Ahmed and his lawyer announce a lawsuit against the British government, and wonders if the ricin is out there in the UK.
[2] Actor Arsher Ali took a 'method acting' approach to his role and as a result, he did not speak to David Oyelowo between takes so as not to break character.