Fergus trained at Trinity College Dublin in Drama and Theatre, Exeter University in Shakespearian Theatre. He is an Irish actor, living in London.
Theatre credits include: Merry Wives of Windsor; All's Well that Ends Well; The Winter's Tale; Twelfth Night (Cambridge Shakespeare Festival). He has performed in several productions of the pantomime Snow White as one of the Seven Dwarfs including in Richmond Theatre (2014), Stockport Plaza (2015), Shaw Theatre (2016) and Middlesbrough Theatre (2017).
Television credits include: Game of Thrones (HBO); The Tudors (Showtime); Callins' Kicks (RTE); Camelot (Starz); Fair City (RTE).
Film credits include: Mary Poppins Returns (Disney); Holmes and Watson (Columbia Pictures); The Jungle Book (Warner Brothers); Assassin's Creed (New Regency Pictures); Killing Lionel (Sunsetrider Productions.); Deadly Presents (Bloody Cuts); Your Highness (Stuber Productions).