The new lead detective of Ireland's Criminal Assets Bureau faces an immediate challenge after a co-ordinated cyber-attack targets her agency and Belgium's Counter-Terrorist Unit, seemingly in connection to the Brannigan case. Bibi Melnick resurfaces with some new and crucial information unveiling dark details on how her father-in-law Richard ran his company Trestford and reveals there's a mole in CTU.

Bibi Brannigan's life hangs in the balance when a hitman arrives in Ireland. A PR disaster threatens Frances Swann's plans, forcing her to take drastic action.