Madam Simza Heron, also known as Sim, is a central character in the movie Sherlock Holmes: A Game of Shadows. She is portrayed by Noomi Rapace. Sim is not a character who appears in the Sir Arthur Conan Doyle books, but appears in the film as a Romani gypsy. Sim joins Sherlock and Watson on their journey when she finds people are after her because they think her brother, Ren