A parasitic alien soul is injected into the body of Melanie Stryder. Instead of carrying out her race's mission of taking over the Earth, "Wanda" (as she comes to be called) forms a bond with her host and sets out to aid other free humans.
The Host is a 2013 American romantic science fiction thriller film written and directed by Andrew Niccol, based on the 2008 novel by Stephenie Meyer. The film stars Saoirse Ronan, Jake Abel, Max Irons, Frances Fisher, Chandler Canterbury, Diane Kruger, and William Hurt. It tells the story of a young woman, Melanie, who is captured after the human race has been taken over by parasitic aliens called "Souls". After Melanie is infused with a "Soul" called "Wanderer", Melanie and the alien "Soul" vie for control of her body.