Mark Hamill
"Star Wars: The Force Awakens" cast member Mark Hamill, pictured here at the 2015 San Diego Comic-Con on July 10, recently tweeted a potentially major spoiler for the upcoming film. Getty

While we don’t know much about what will happen in J.J. Abram’s upcoming film “Star Wars: The Force Awakens,” one character’s role has been kept so secret that it’s almost all fans can talk about. With Luke Skywalker (Mark Hamill) being kept completely out of any trailers or teasers for the film, the actor let one key detail about his role slip on Twitter Monday.

The 64-year-old star responded to a fan’s question about his changing facial hair and inadvertently revealed that he just finished a guest role on a TV series that required him to be clean-shaven. As a result, he is now able to grow out the old facial scruff just in time to start work on “Star Wars: Episode VIII,” which he will apparently been a part of.

Now that the actor has finished filming his second appearance as the Trickster on the CW’s “Flash,” he’s free to start growing out his beard again, which he has to do to play Luke in the new movie. As CinemaBlend notes, this isn’t the first time that rumors have circulated that Hamill’s character will appear in the Rian Johnson’s 2017 follow up to “The Force Awakens." However, this does appear to be the first direct confirmation from anyone affiliated with the movie that Hamill’s iconic character will survive the events of episode VII. However, it is worth mentioning that the “Star Wars” universe has set up the idea of character’s returning as ghosts in the past. After all, Alec Guinness’ Obi-Wan Kenobi died in the first “Star Wars: A New Hope” movie, only to return as a Jedi specter in “Empire Strikes Back.”

Many fans were worried about the fate of Luke Skywalker in the upcoming trilogy, given that Abrams said he wouldn’t appear in any promotional capacity leading up to the film. He recently teased to that the reason for the secrecy has to do with the plot of the film. It wasn’t long before fans took this to mean that perhaps Luke Skywalker’s big reveal is that he ended up on the Dark Side after all.

While it may seem like a bad idea for the new trilogy to open by completely undoing the emotional journey that the character went on in the original trilogy, Slate notes that there’s precedent to explain Luke turning to the dark side of the force that dates back to his role in “Return of the Jedi.” It’s possible that Abrams is saving Luke’s Sith-like look for a big dramatic reveal in which newcomers and old friends alike realize that he’s not the man that helped take down the evil Galactic Empire all those years ago.

"Star Wars: The Force Awakens" hits theaters Dec. 18. Do you think Luke will return as a villain in “Star Wars: The Force Awakens”? Comment below or tweet your every “Star Wars” thought to @TylerMcCarthy.