A family finds themselves terrorized by their eight-year-old son's imaginary friend.

The housewife Beth and the engineer Kevin are happily married with the eight-year-old son Joshua "Josh", who is a lonely boy with no friend at school. Beth's mother is terminal, and her sister Jenna is estranged from her mother. One day, Josh has an imaginary friend, Z, and Beth becomes worried about the situation. When Josh becomes aggressive and is suspended from school, Beth convinces Kevin to have an appointment with the psychiatrist Dr. Seager. He does not find any great issue with Josh until he hears the name of his friend, Z. Beth looks for her friend Georgia and asks whether Josh may play with her son. Soon Josh pushes the boy from the staircase, and he goes to the hospital seriously wounded. Soon Beth and Kevin see Z and when she finds a video footage that belonged to her mother, who has deceased, she hears the name of Z. She calls Dr. Seager, who tells her that she created Z when she was a girl, and now he seems to be using Josh to reach Beth since he is interested in breeding her.—Claudio Carvalho, Rio de Janeiro, Brazil