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Actor Gerard Butler got into a sea of trouble Monday after he was pulled underwater and had to be rescued during production of a new movie about surfing in California.

The San Jose Mercury News reported that the 42-year-old Scottish actor was paddling out with three professional surfers when waves taller than 15-feet broke in front of them, sending the "300? actor and the surfboard he was tethered to under the water.

A water safety guard on a jet ski immediately rushed to the actor's aid. Though shaken, Butler was not injured nor were any of the surfers who accompanied him. Still, he went to Stanford Medical Center for observation and was later released.

Competitive surfer Zach Wormhoudt told The San Mateo County Times newspaper that Butler had not surfed much before the movie but had been working on his skills.

"Everything he was doing was within reason," Wormhoudt said. "We took, like, four to five pretty big waves on the head. Basically there's nothing you can do.

"It was intense for myself, and I've been through a lot out there," he added.

Butler is starring in the movie, "Of Men and Mavericks," the story of surfer Jay Moriarty, who conquered the Mavericks, a surfing location in Northern California. Moriarty died in a free-diving accident shortly before his 23rd birthday. Butler plays surfer Frosty Hesson.