Gran'pa is ninety-five, possessed of 100,000 pounds, a fertile imagination, and a good physique. He sees in the papers accounts of Professor Vornoff's theory of rejuvenation by means of gland-grafting.
Nothing will satisy him but that the experiment should be made upon himself. He acquires a gorilla, a hefty murderous brute, and the operation is performed with success. That is only the beginning.
He next determines to dig out an old love, and make her young too; and Sally, a dear old lady of seventy, arrives upon the scene.
Inspired to philanthropy by the thrill of regained youth, Gran'pa decides to take a hundred or so old men to Africa, capture a like number of gorillas, and borrow their glands.
There are thrilling adventures with the gorillas, whilst the old gentlemen supply the comedy--there are not enough glands to go round. The result of the operations is a surprise to all, particularly to the old gentlemen themselves.