A teenager must cope with a disease that causes himself to age at an astronomical rate.
| Actor | Role |
|---|---|
 Ralph MacchioBilly Grier | Billy Grier |
 Betty BuckleyNancy Grier | Nancy Grier |
 Hal HolbrookGrandpa Grier | Grandpa Grier |
 Season HubleyPhyllis | Phyllis |
 Jeffrey TamborDr. Lindsey | Dr. Lindsey |
 Lawrence PressmanFrank | Frank |
 Conchata FerrellDr. Gardner | Dr. Gardner |
 Ed LauterMr. Grier | Mr. Grier |
 Viveca LindforsDr. Rice | Dr. Rice |
 Laura DernCrissy | Crissy |
 Betty PhillipsMary Whitelaw | Mary Whitelaw |