ITV's new four-part MI5 drama Betrayal premieres on February 8, 2026, starring Shaun Evans as a mid-career intelligence officer under investigation. The series explores themes of loyalty and deception amid a suspected Iranian plot on UK soil. Evans leads alongside Romola Garai, Zahra Ahmadi, and Nikki Amuka-Bird in this suspenseful thriller.
ITV's Betrayal marks the network's latest entry into spy dramas, airing at 9pm on Sunday, February 8, 2026, on ITV1 and ITVX. The four-part series replaces After the Flood in the primetime slot and centers on John Hughes, portrayed by Shaun Evans, a seasoned MI5 officer from a working-class background who rose to prominence during the 1990s war on terror. John's life unravels when he meets a British-Iranian informant linked to Stockport gangland, who claims knowledge of a UK-targeted plot. Before sharing details, the informant is killed, and John fatally shoots the assassin in self-defense, triggering an internal investigation.
As scrutiny intensifies from superiors like Simone Grant (Nikki Amuka-Bird), John's wife Claire (Romola Garai), a high-pressure GP, struggles with the secrecy eroding their marriage. Claire, initially excited by her husband's spy life, now feels betrayed by withheld truths. John finds an ally in Mehreen Askari-Evans (Zahra Ahmadi), a confident British-Iranian MI6 operative taking over his duties. Convinced of a hardline Iranian regime faction's involvement—and possible enemies within MI5—John races to avert an attack.
Zahra Ahmadi described Mehreen as "supremely confident, very comfortable in herself and her abilities... a real grafter, passionate about what she believes in." Nikki Amuka-Bird, playing Simone, the Head of State Threats, noted the role's demands: "She's in charge of security for the state... has to stay clear headed, have excellent judgment and be able to analyse complex situations at the drop of a hat, every day."
The ensemble includes Gamba Cole as tech expert Rudy Kember, Omid Djalili as Iranian General Qasem Asadi, and supporting roles by Matthew Tennyson, Hayley Tamaddon, and others. Evans, known for Endeavour, and Garai, from Atonement and Vigil, bring depth to this tale of personal and professional isolation in intelligence work.