"Viaje al centro de la tierra" is a Spanish family adventure series about a cheerful boy named Diego. His parents send him to a summer camp run by the eccentric scientist Pompilio Calderon. There, Diego and his new friends find a locket that once belonged to his grandmother, Pilar. Trying to unravel the history of this ornament, they embark on an incredible adventure in a parallel dimension to save our planet from a global catastrophe.