Tessa is a news editor for the BBC in Belfast who holds a master's degree in history and politics. As a divorced single mother, she carefully structures her life to provide a safe, predictable environment for her six-month-old son, Finn. Her carefully maintained separation from Northern Ireland's political violence shatters when police identify her younger sister in footage of an IRA armed robbery.

Marian is Tessa's younger sister who works as a paramedic in Belfast. Known for her relaxed, amused expression and active social life, she secretly maintains a highly dangerous double life within the IRA. Groomed into paramilitary service after a personal tragedy, she eventually risks everything to act as an inside informant to protect the fragile peace talks.

Eamonn is an attractive, sharply dressed MI5 agent operating in Northern Ireland. Tasked with handling civilian informants embedded inside paramilitary groups, he uses charm and vague promises of protection to secure cooperation. He views his assets with calculated pragmatism, prioritizing state intelligence gathering above individual safety.

Seamus is a Marxist theorist and highly active recruiter for the IRA. He deliberately cultivates a harmless appearance, often wearing a beige suit that makes him look unassuming. Behind this mild exterior, he operates as a ruthless strategist who grooms vulnerable youths and relentlessly scouts for vulnerable police officers to target.

DI Fenton is a veteran police investigator in his fifties with a lined, expressive face and a crumpled suit. Having survived the loss of numerous colleagues to paramilitary violence over his long career, he is deeply skeptical of civilian claims of innocence regarding IRA affiliations and doggedly pursues the truth behind the robbery.

Damian is an active member and designated sniper for Marian's IRA unit. He comes from a family deeply entrenched in republican paramilitary activities, making his allegiance absolute and unquestioned by the organization's leadership. He relies on specific logistical supplies to carry out his operations.

Niall is a younger member of Marian's IRA unit. Having grown up as an orphan, he views his paramilitary cell as his true family. He is eager to conduct operations and displays an aggressive readiness for violence, though he balances this with a softer, protective attitude toward his immediate comrades.

Finn is Tessa and Tom's six-month-old son. He spends his days going to daycare, playing with neighbors, and serving as the absolute center of his mother's world. His existence inadvertently complicates his family's safety in a politically volatile city.

Tom is Tessa's ex-husband who caused the end of their marriage by cheating on her with a colleague while she was pregnant. He maintains shared custody of their son and exercises strict legal rights over where the child is permitted to live, directly obstructing attempts to flee the country.

Tessa's mother is a blonde, sturdy woman with a brisk warmth who shares a household with her daughter and grandson. A devout Catholic, she works as a domestic cleaner to support herself. She possesses a remarkable capacity for religious forgiveness, which colors her reaction to familial betrayals.

Cillian Burke is a notorious and highly prominent IRA figure. He maintains a massive profile in Belfast, commanding significant respect and fear within republican circles while managing to avoid long-term legal consequences for his suspected actions.

Nicholas is a journalist and correspondent for the BBC in Belfast. He works closely with his editorial team to select viable political topics and interview subjects for their broadcasts, providing a grounding professional presence.

Rebecca Main is a British justice minister who publicly insists that the United Kingdom will never bend to terrorism. Privately, she betrays her genuine fears regarding the region's instability by wearing bulletproof vests during television broadcasts.

Sophie is a civilian neighbor living in Greyabbey. She is a reliable local contact who frequently assists with childcare and maintains the illusion of a normal, quiet domestic life completely separate from the city's paramilitary underbelly.

Poppy is a young girl living in Greyabbey who participates in local neighborhood playdates, representing the innocent civilian life that families strive to protect.

Aoife is a member of the Daly extended family whose marriage choice directly links her relatives to prominent paramilitary figures, demonstrating how intertwined the community is with the IRA.

Colette works at the BBC broadcasting studio. Unbeknownst to her civilian colleagues, she secretly monitors the guest list and feeds the IRA information about important political figures visiting the facility.

Lord Maitland is a wealthy British aristocrat who owns a manor in Northern Ireland. Because he frequently visits the region for fishing holidays, republican paramilitaries view him as a symbolic target for violence.