Oxly's hopes are raised when it appears that the aged Rudolph is bounding around like a youngster, but it is revealed that Rudolph's numbered uniform was inadvertently switched with that of the younger, mischevious Esther.
Oxly shows Barnaby the ad campaign he has devised for the formula, which he has named B-4, but Barnaby urges him to be patient. The elderly Oxly hopes that Barnaby's formula will be financially successful, and will enable him to pursue his curvaceous secretary, Lois Laurel.
One morning, when Barnaby arrives at the Oxly Chemical Factory, where he works as a free-lance scientist, he is summoned to president Oliver Oxly's office. Barnaby is encouraged by his wife Edwina, who loves her brilliant husband despite his eccentric behavior. Absentminded scientist Barnaby Fulton is discouraged when his formula, which he hopes will reverse the ill effects of aging, proves ineffective on his test chimpanzees, Rudolph and Esther.
