Starring Robin Williams, Diane Lane and Brian Kerwin Directed by Francis Ford Coppola Jack Powell (Williams) appears to be an average, middle-aged forty year old man – who plays with G.I. Joe and wears Power Ranger pajamas – but Jack is only 10-years-old. He suffers from a genetic disorder that causes him to physically age four times faster than a normal person. Fearing ridicule from the outside world, Jack's parents have kept him secluded in their home. Now he's about to embark on the greatest adventure of his unusual life - he's about to enter the fifth grade.