Beth is illiberal but principled and not at all establishment. She's opinionated and a provocateur who never plays by the rules. She joined M.I.5 when she was young and was trained by them, but was kicked out due to her inability to follow orders. Harry was the officer who made that decision. He saw how volatile she could be and that she wasn't mature enough to be a spy. Her reputation in the field is what attract M.I.5 to Beth. She wants to go back and agrees to because of her own agenda.
A vicar's daughter brought up in Isleworth, West London, Sophia Myles was spotted by a British casting director at the age of sixteen in a school play and offered a small part in the television version of The Prince and the Pauper. She went onto star in the critically acclaimed BBC telefilm Colditz with Damian Lewis. Then she played the female lead in the Terry Zwigoff film Art School Confidential with Steve Buscemi and John Malkovich and starred as "Isolde" in the 20th Century Fox feature Tristan & Isolde for director Kevin Reynolds and producer Ridley Scott.