While many celebrities in the entertainment industry are disparaged for their out-of-touch nature and "cushy" lifestyle, rest assured that not all film stars have it so easy. In fact, some actors are more than willing to suffer for their craft. Perhaps there is no better example of this than the cast of The Blair Witch Project.

The film is 81 minutes of pure stress and terror as audiences watch what can safely be considered the worst camping trip in history. The movie focuses on three film students attempting to make a documentary about a local legend, known as The Blair Witch.

According to an interview with Rolling Stone, the exhausted and dejected performances from the film's three stars weren't simply invented. The film's producer claimed that preparation during filming was actually based on an army training program.

"I had gone through the army's SERE school," said producer Gregg Hale. "It stands for survival, evasion, resistance, and escape. You go through this four-day escape and evasion thing, with guys chasing you and stuff. I knew they weren't going to kill me, I knew these guys were American soldiers playing a part, I knew that in two and a half or three days of this it would be over, but at the same time, I was terrified. That kind of sparked the thought of 'Well, why don't we apply this kind of total-immersion scenario to the actors?' If we've physically and mentally abused them enough in the process of getting them up to those intense moments at the end, then they'd be able to tap into emotional places that they wouldn't otherwise be able to tap into."

Of course, the actors' safety was guaranteed, and no one was actually at risk. But to guarantee a genuine performance, drastic methods were implemented by crew members. "We did keep them isolated, we harassed them at night," said Hale. "We deprived them of sleep, we made them move a lot during the day. Then, at the end, we slowly fed them less and less, and they never knew what was happening. They were always off-balance."