Updated: December 12, 2024

In the pilot episode, "The Lady in the Bottle", astronaut Captain Tony Nelson, United States Air Force, is on a space flight when his one-man capsule Stardust One comes down far from the planned recovery area, near a deserted island in the South Pacific. On the beach, Tony notices a strange bottle that rolls by itself. When he rubs it after removing the stopper, smoke starts shooting out and a beautiful Persian-speaking female genie materializes and kisses Tony on the lips, shocking him.

They cannot understand each other until Tony expresses his wish that "Jeannie" could speak English, which she then does. Then, per his instructions, she "blinks" and causes a recovery helicopter to show up to rescue Tony, who is so grateful he tells her she is free. But Jeannie, who has already fallen in love with Tony after being trapped for 2,000 years, re-enters her bottle and rolls it into Tony's duffel bag so she can accompany him back home.

In one of the early episodes Jeannie helps to break up Tony's engagement to his commanding general's daughter, Melissa, who, along with the general, is never seen or mentioned again. Producer Sidney Sheldon realized the romantic triangle between Jeannie, Tony, and Melissa would not play well in the long run.

At first Tony keeps Jeannie in her bottle most of the time, but he finally relents and allows her to enjoy a life of her own. However, her life is devoted mostly to his, and most of their problems stem both from Jeannie's love for him and her often-misguided efforts to please Tony, even when he doesn't want her assistance. Tony's efforts to cover up Jeannie's antics, out of fear that he would be dismissed from the space program if her nature were discovered, constantly puts him under the scrutiny of NASA's resident psychiatrist (and Tony's commanding officer), U.S. Air Force Colonel Dr. Alfred Bellows. A running theme throughout the series has Bellows as the only eyewitness to Jeannie's antics while Tony ( and sometimes his best friend and fellow astronaut, United States Army Captain, later Major, Roger Healey ) are also present. Tony offers far-fetched explanations to Bellows, who then tries to prove to his superior officers that Tony is either crazy or is hiding something. But his efforts typically backfire and in the end his superiors never buy it; after Bellows is foiled, he proclaims, "He's done it to me again!"