The Freeman family have been invited to the Toneybee Institute in rural Massachusetts to participate in a research experiment. They will live in an apartment on campus with Charlie, a young chimp abandoned by his mother. The Freemans were selected for the experiment because they know sign language; they are supposed to teach it to Charlie and welcome him as a member of their family. Isolated in their new community, the Freemans come undone. And when their daughter, Charlotte, discovers the truth about the Institute's history of questionable studies, the secrets of the past begin to invade the present.
