Guest Stars Conor Mullen as Frank Ahern Carrie Crowley as Mairead Noonan Justine Mitchell as Elaine Lynch Elijah O'Sullivan as Jacob Dwyer Éanna Hardwicke as Joe Ryan James O'Donoghue as Calum Dwyer Hazel Doupe as Ingrid Jensen Hugh O'Conor as Dr. Kevin Lochlainn O'Mearáin as Rory Dwyer Stuart Graham as Denis Ahern Michael Patric as Sgt. Paudie Manning Thomas Levin as Carl Jensen Carolyn Bracken as Sandra Dillon Noah James Flynn as Young Calum Huey O'Meara as Young Jacob Domhnall Herdman as Biter Cathal Greene as Driver Cian Hughes as Finn Tanja Johannsen Walsh as Danish Radio Presenter