The ruse was so successful that it worked until the actors playing Han, Luke, and Leia arrived on set, at which point it became obvious to bystanders that this was not a low-budget horror film, but the next Star Wars film.
While Return of the Jedi was released in 1983, the term "Blue Harvest" lived on in Star Wars lore. 1. Blue Harvest
The strategy was highly effective, particularly when filming on location, such as in the redwood forests near Crescent City, California (used for Endor), and the Buttercup Valley in Arizona (used for Jabba the Hutt's sail barge scenes). The ruse was so successful that it worked