After a long and unsuccessful period trying to have a family, Claire (Catherine McCormack) and Adrián (Jordi Mollá) finally adopt a girl. The coming of Isabel is desired by the whole family but making a six-year-old girl with a past of her own fit into her new life might be something more complicated than they expected.
Strange things start to happen from the moment Isabel and her imaginary friend, Stevie, come to live with them. The situation escalates when Stevie’s behavior becomes aggressive. Only Claire and Isabel know that Stevie is more than just a creation of Isabel’s imagination. Without help from others, Claire will do everything to find out who Stevie is and what he wants. Perhaps if she succeeds, she will be able to recoup their lives and have the family she had desired for so long.