This is a far cry from his "High School Musical" days! Zac Efron was out of his element in new series "Running Wild With Bear Grylls," where he ate a worm and completed several other daring tasks. Did you catch Monday night's episode?

"A reliable source of food is always under the ground, in the earth - good old worms," the survival expert advised Efron.

The heartthrob was unable to locate food on the two-day challenge, and was also seen jumping out of a helicopter, rappelling down a waterfall and crawling across a rope over the Catskill Mountains.

"Just remember you've got to chew it - you don't want it wriggling all the way. Otherwise it might crawl out of like a weird orifice or something," Grylls said.

"The Lucky One" star pulled through, though admitted it was not the easiest thing he's ever done.

"Watching worms boil in egg is just disgusting, there's no way around it. They're just writhing in worm pain. It's kinda sad - but to survive sometimes takes a couple of worms," Efron revealed of the experience.

"Sometimes I cook up these wilderness meals and get quite excited, I think, 'You know what, this is gonna be amazing."'

"But I'm not gonna sugarcoat it - this is one of the ones that I know is gonna suck," the actor concluded.

Later in the episode, Grylls revealed to Efron what he's afraid of.

"I can't dance," he confessed. "I'm not joking. The fear of God would come over me."

The survival expert also explained how he felt the star would handle the challenge.

"He's used to the screaming of millions of fans - but this time it's Zac that's gonna be doing the screaming," Grylls joked.

Can you believe Efron ate worms to survive? Let us know your thoughts in the comments section below.