Twin brother and sister Dipper and Mabel Pines are in for an unexpected adventure when they spend the summer with their great uncle in the mysterious town of Gravity Falls, Oregon. Upon their arrival, Dipper and Mabel's huckster great uncle, also known as Grunkle Stan, enlists the siblings' help in running The Mystery Shack, a fun tourist trap he owns that overcharges unsuspecting customers. Although Dipper and Mabel quickly discover The Mystery Shack itself is a hoax, they sense there is something strange about their new town and together they begin to unlock the secrets of Gravity Falls.