Back when "Star Wars" was still in its early stages, Mark Hamill, who plays Luke Skywalker, initially thought that he would be playing a supporting role to Harrison Ford's Han Solo.

In a typical Hollywood setup, the casting process usually operates in secrecy. When actors and actresses come in to audition for a role, they are given just the right amount of information for their audition. It's uncommon for up-and-coming thespians to see an entire script.

That's why when Hamill came in to audition for the role of Luke, he was clueless as to who the character really was and thought at first that Ford's character was the lead of the film.

Hamill recently celebrated his 66th birthday by doing an interview with StarWars.com. The actor discussed the past and future of his career with the film franchise.

In the interview, Hamill divulged that he at first, he thought that he was Han Solo's sidekick; he only found out that he was going to play the main character when he read the title of the script, which was only given to him after he got the job.

During the casting process, there wasn't a lot of communication and Hamill had to piece things together. He was surprised after finally getting the script.

"I open the title page and it says, 'The Adventures of Luke Starkiller, as Taken from the Journal of the Whills, Saga Number One: The Star Wars.' ... So I thought, 'I'm playing his sidekick, right?'" he explained.

The long title of the script was the original title for the movie. As the movie started shooting, a lot of things changed, including the title which had been shortened to "Star Wars."

Since then, Luke Skywalker has undoubtedly become one of the most iconic fictional characters in the history of cinema.