Generate a question about the following movie plot: John Murdoch (Rufus Sewell) awakens in a hotel bathtub, suffering from amnesia. He receives a phone call from Dr. Daniel Schreber (Kiefer Sutherland), who urges him to flee the hotel to evade a group of men who are after him. During the phone talk, Murdoch discovers the corpse of a brutalized, ritualistically murdered woman, along with a bloody knife. He flees the scene, just as the group of men (known as the Strangers) show up to investigate the room. Eventually Murdoch learns his own name, and finds he has a wife named Emma (Jennifer Connelly). He is also sought by police inspector Frank Bumstead (William Hurt) as a suspect in a series of murders committed around the city, though he cannot remember killing anybody. While being pursued by the Strangers, Murdoch discovers that he has mind powerswhich the Strangers also possess, and refer to as "tuning"and he manages to use these powers to escape from them. Murdoch explores the city, where nobody realizes that it is always nighttime. At midnight, he watches as everyone except himself falls asleep as the Strangers stop time and physically rearrange the city as well as changing people's identities and memories. Murdoch learns that he comes from a coastal town called Shell Beach, a town familiar to everyone, though nobody knows how to leave the city to travel there, and all of his attempts to do so are unsuccessful for varying reasons. Meanwhile, the Strangers inject one of their men, Mr. Hand (Richard O'Brien), with memories intended for Murdoch in an attempt to predict his movements and track him down. Murdoch is eventually caught by inspector Bumstead, who acknowledges he is innocent, and by then has his own misgivings about the nature of the city. They confront Dr. Schreber, who explains that the Strangers are endangered extraterrestrial parasites who use corpses as their hosts. Having a hive mind, the Strangers have been experimenting with humans to analyze their individuality in the hopes that some insight might be revealed that would help their race...
Who holds Emma hostage?