The pilot took place in a triplex apartment building in North Hollywood called "Hacienda Palms" but the eventual series was at an apartment house in Santa Monica.
John Ritter's character in the pilot was named David Bell and he was an aspiring filmmaker. In the eventual series, Jack Tripper is an aspiring chef.
Joyce DeWitt and Suzanne Somers were not yet cast in this pilot edition. Valerie Curtin and Susanne Zenor assumed those roles in this episode, although the characters had different names.
The theme song has no real lyrics. The singers just sing "da-da-da-da-da-dum".
The apartment set is slightly different than the one eventually used in the series. The kitchen and living room are the same. But the locations of the girls' room and the bathroom were switched for the series and Jack's room was adjacent to the window rather than the bathroom.