MariaDoyleKennedy_82550tEXCLUSIVE: Former Tudors co-star Maria Doyle Kennedy is back at Showtime, now joining the cast of another drama series, Dexter. The Irish actress-singer, who played Henry VIII’s (Jonathan Rhys Myers) first wife Catherine Aragon in the first season of The Tudors, will recur on Dexter’s upcoming 5th season as an Irish nanny Dexter Morgan (Michael C. Hall) hires. The show also recently announced that Julia Stiles will join Dexter next season in a season-long arc.