After months of training, former Long Island homicide detective Maggie D’arcy is now officially a Garda. She’s finally settling into life in Ireland and so is her teenage daughter, Lilly. Maggie may not be a detective yet, but she’s happy with her community policing assignment in Dublin's Portobello neighbourhood.

When she and her partner find former model and reality tv star Jade Elliot murdered—days after responding to a possible domestic violence disturbance at her apartment—they also discover Jade's toddler daughter missing. Shorthanded thanks to an investigation into a gangland murder in the neighbourhood, Maggie’s friend, Detective Inspector Roly Byrne, brings her onto his team to help find the missing child. But when a key discovery is made, the case only becomes more confusing—and more dangerous. Amidst a nationwide manhunt, Maggie and her colleagues must look deep into Jade’s life—both personal and professional—to find a ruthless killer.