ITV2's sexually-charged drama, Secret Diary OF A Call Girl, follows the double life of a beautiful young prostitute working the streets of London. By day, Hannah (Billie Piper, DR Who) is a respectable legal secretary who works long hours to make ends meet. By night she's Belle, a ruthless, money-hungry hooker who will do anything to satisfy her clients' basest fantasies. A professional in every sense of the word, Belle slips with seeming ease from the role of girl-next-door to high-heeled dominatrix, taking care never to become emotionally involved with her clients. But the constant pressures of keeping her two lives separate begins to take its toll, and in an unguarded moment with a handsome stranger, Belle lets slip her true identity. From then on, he only wants to be with Hannah... Based on the internet blogs of London call girl Belle de Jour, this provocative first series presents a very human angle on the sex trade.