The absence of Mark Hamill from the "Star Wars: The Force Awakens" promotional materials has sent fans searching for even the tiniest clues to Luke Skywalker's whereabouts. Did he turn to the Dark Side? Is he in hiding from the First Order?

You'll likely have to wait until the film arrives in theaters. But whatever you do, don't ask Hamill for any hints because, as he explains in a new video, "I'm not even authorized to tell you I'm in Episode VII. It's all ... secret." Of course, he laughed as he said that, so he's probably kidding. However, his non-disclosure agreement is no joke.

"It's crazy, though, this 'NDA' stuff -- non-disclosure agreement -- where you're not allowed to talk about anything," the "Star Wars" veteran tells Games Radar. "I have something coming out where there's an amount of money that if it leaks because of me, I don't get that payment. If I keep it a secret til the day it comes out, I get that payment."

"But, you know, I'm good about keeping secrets," he continues. "I'm proud of the fact that I knew a year and half before anybody else that he was actually Dad Vader."

"Star Wars: The Force Awakens" opens Dec. 18 in North America, after which we'll know what Hamill knows. Probably.