We know Indiana Jones is terrified of snakes. We know his dad never would have made it past those rats. What we didn’t know until now was what scared his son.

“Being able to effortlessly merge in,” Shia LaBeouf earnestly said when asked what his biggest challenge was as shooting began for “Indiana Jones 4.” “You don’t want to be a speed bump; you just want it to stay the way it’s been going. It’s the most beloved franchise [of all time]. You don’t want to be the guy that brings the house of cards down. I’m just looking to survive and stay afloat, and not get fired.”

It’s hard not to root for the kid when he smiles and squeals like he just won the geek lottery. “I’ve never experienced anything at this level. It’s all nuts,” LaBeouf exclaimed. “I feel crazy right now. I feel like a crazy man. I’m looking forward to thousands of things.”

One thing the 21-year-old star is looking forward to post-Indy, he said, was a re-teaming with “Disturbia” director DJ Caruso, on a recently announced project called “Eagle Eye,” about a young man and a single mother who are framed as terrorists and forced to join a group with plans to kill a political figure.

“DJ Caruso is still the greatest director I’ve ever worked with. I’ve had the most fun with him,” Shia gushed. “[The film was] Steven Spielberg’s love-child. He was going to direct that, but then he decided to do Indy. So we’re going to get a good cast together and try to make a good movie with the little family that we’ve built.”