Wanderer is the main character, a parasitic alien "soul" inserted into Melanie Stryder's body in the first scene. She received her name due to the number of planets she has lived in, having never settled on one she truly liked. She is later nicknamed "Wanda" によって Mel's Uncle Jeb and her brother, Jamie. Initially only interested in enjoying her new life, Melanie's refusal to die off as expected forces her to make choices she otherwise would not have, and she slowly developes sympathy for the human characters, eventually acknowledging that they have a right to their own lives, and attempting to sacrifice herself so that Melanie can have her life back. She is uncomfortable with violence, and enjoys storytelling, a role she is indicated to have held in several 前 hosts. Physically, her capabilities are determined によって her host.