Guest Stars Lisa Hogg as Emma Riley Lloyd Hutchinson as Supt. Shanahan Barry McGovern as Dr. James Whelan Seán T. Ó Meallaigh as Jack Lucey Jade Jordan as Donna Walsh Andrew Bennett as Donal Riley Hannah James-Scott as DG Angela Webster Orla Charlton as Deirdre McGuire Mae Higgins as Young Fia Rebecca Hanssen as Carrie Hurley Brendan Conroy as Fergus Slattery Youssef Quinn as DG Luke Gannon Natalie Radmall-Quirke as Serena Reid Frank Blake as Sean McGuire Megan O'Connell as Lynette Brian Doherty as Ed Donoghue Dara Devaney as Liam McArdle Grace Collender as Chloe Whelan Lynn Rafferty as Zara Bailey Claire J. Loy as Breda Gleeson Phil Kelly as Gerard