Walker Leads Shark Expedition

The actor spent 11 days off the coast of Mexico with a film crew and shark experts shooting footage of the sea monsters for National Geographic channel's Expedition Great White.

The former marine biology student admits the experts onboard for the mission weren't quite sure what to make of their Hollywood guest at first.

He tells TV Guide magazine, "They were like, 'S**t, we've got an actor coming on the boat.' It's that preconceived notion of Hollywood that I guess most of us deserve."

But the shark chasers quickly realised Walker knew just about as much as they did when he started talking about his love of sharks - and now he's joining another sea mission later this month (Nov09) - on the hunt for a giant squid.

Walker's shark mission airs in America on 16 November (09).