Kelly Mathieson biography Kelly Mathieson is a professional theatre actress who is currently appearing as Christine Daae in the long-running production of The Phantom Of The Opera at Her Majesty’s Theatre. This role marks her West End debut. Growing up in Scotland, Kelly started training in ballet when she was only two years old. She later trained with the Scottish Ballet company. Kelly also went to the Royal College of Music and graduated with a BMus Honours in 2015. Theatre: Her work in theatre includes portraying Tonia in Dr Zhivago, Pamina in Die Zauberflote at Pugulia Opera Festival (2016), Actress in Agrippina at the Theatre an der Wien (opera, 2016), Barbarina in Le Nozze with the Scottish Opera (2017), and Johanna in Sweeney Todd at the Huddersfield Town Hall (musical, 2018).