As MGM prepares to release a 3-D version of the 1939 classic “The Wizard of Oz” to theaters on Sept. 20, the film stands at the doorstep of a milestone: the 75th anniversary a beloved and influential film and, according to the Library of Congress, the most-watched movie of all time.

With the exception of superstar Judy Garland, the cast of the movie was made up of character actors whose careers were eclipsed by the shadow of Oz. Director Victor Fleming was a filmmaker whose movies are remembered better in history than he is. Even choreographer Busby Berkeley, who worked on some of the dance numbers for the film (his deleted Scarecrow scene can be viewed at the Turner Classic Movies website), is remembered better for other films.

So what is it about the classic film that has held the love and attention of audiences for such a long time?

Fans of the land of Oz would say that the magic of author L. Frank Baum’s original story has much to do with its success. The magic of that world was too much to remain contained within a single film, as has been proved by the number of times that the world of Oz has been remade, rebooted, altered, borrowed and paid homage to since Baum’s original story “The Wonderful Wizard of Oz” was published in 1900.

Here’s a quick walk through the history of the magical land of OZ on film and television:

“The Wonderful Wizard of OZ” (1910)

Many people believe that the 1939 version of the film was the first one ever put to film. Not only did it miss that honor by 29 years, but this original version, produced by a prolific film company called Selig Polyscope, had a sequel called “Dorothy and the Scarecrow in Oz” later that same year. The film series continued past that, with the sequels — “The Land of Oz,” “The Patchwork Girl of Oz” and “The Magic Cloak of Oz” — being produced and sometimes written by Baum himself under The Oz Film Manufacturing Company. The series continued until 1914, with the last installment, “The New Wizard of Oz,” being written, produced and directed by Baum.

“Return to Oz” (1985)

Though television would visit the land of Oz infrequently in animation (“Tales of the Wizard of Oz” in 1961) and filmed versions of live stage shows (“The Marvelous Land of Oz” in 1981), it would be 46 years before a studio would produce another big-budget story that brought the land of Oz to the big screen. Directed by Oscar-winning editor Walter Murch and written by Gill Dennis (who would later co-write the Oscar-winning Johnny Cash biopic “Walk the Line”), “Return to Oz” was decidedly darker than the original 1939 musical and stayed closer to the content of the original books. Though not the success Disney had hoped for upon release (according to Box Office Mojo, the $25 million film had a domestic return of only $11 million), it has earned a devoted following.

“The Dreamer of Oz” (1990)

Following a renewed interest in the television movie-of-the-week format and “The Wizard of Oz” on its 50th anniversary, NBC aired “The Dreamer of Oz,” a story of the creation of Oz by Baum. Starring John Ritter as Baum and written by classic science-fiction author and “Twilight Zone” writer Richard Matheson, this sweet film reveals the story behind the inspiration for Dorothy, and the hilariously simple method by which he named the land of Oz.

“Lion of Oz” (2000)

After Baum, the original author of the series, passed away, the popularity of Oz never waned, and the work of traveling back to Oz to bring new generations more stories became a family business. His son, Frank Joslyn Baum, wrote “The Laughing Dragon of Oz." His great-grandson, Roger S. Baum, continued the tradition. His novel “Lion of Oz and the Badge of Courage” was turned into an animated feature film with voice talents as varied as Dom DeLuise, Bobcat Goldthwait, Jason Priestley and Tim Curry. The sequel film, “Legends of Oz: Dorothy’s Return” (based on Roger Baum’s book), is in production and expected out next year.

“Tin Man” (2007)

Before the Sci-Fi Channel changed its name to Syfy and began producing giant-hybrid-monster movies, it took a chance on a steampunk reinvention of “The Wizard of Oz” in a mini-series called “Tin Man.” Created and written by Steven Long Mitchell and Craig W. Van Sickle (who had cut their teeth on television sci-fi previously with shows like “Alien Nation” and “The Flash”), the show was influenced in equal part by “The Wizard of Oz,” “The Matrix” and video game storytelling.

“Oz the Great and Powerful” (2013)

This year brought a lot of attention back to the land of Oz, from the constant tease of the Wizard’s appearance on ABC’s “Once Upon a Time” to the news of four upcoming television concepts based on the Oz books (a post-apocalyptic action mini-series, a medical drama and two dark fantasies), but the one that has garnered the most attention was the James Franco film “Oz the Great and Powerful” from “Spider-Man” director Sam Raimi. With special effects that have finally caught up to the ceaseless imagination of the Baum legacy, and a worldwide gross of nearly $500 million, “Oz the Great and Powerful” shows that modern audiences aren’t so jaded that they can’t be taken in by the magic all over again.

One hundred thirteen years after the first book was published and 75 years after the classic film was released, fantasy fans are still clamoring for another trip down the yellow brick road.

Chris and Kathleen Vander Kaay are screenwriters and authors who live in Central Florida.