In February 2001 Stilley began working briefly as a model in Milan, Italy with Elite Model Management but moved to London by the end of the year to pursue her acting career. Her first acting job was the lead Actress in the controversial 2004 British film 9 Songs, directed by Michael Winterbottom. According to the Guardian, 9 Songs was the most sexually explicit mainstream film to date, largely because it includes several scenes of real sexual acts between Stilley and her co-star, English actor Kieran O'Brien. The film screened in Cannes Film Festival and Sundance Film Festival and had a world-wide theatrical release. Stilley asked that Director Michael Winterbottom refer to her simply by her character's name in interviews about the film at the beginning to protect the artistic integrity of the film. Her second credit solidified her standing in Britain's indy film scene starring in the satirical comedy Nathan Barley directed by Chris Morris for British television.