Just how bad was Shia LaBeouf's hand injury, and how did it threaten Transformers 2?

Everyone knows by now that Shia LaBeouf injured his left hand in an auto accident last July. But it's only now becoming apparent just how serious that injury was and how it affected the production of Transformers: Revenge of the Fallen, which was in the middle of shooting when the accident happened.

Director Michael Bay, speaking to reporters in Beverly Hills, Calif., last week, recalled how the injury threatened to shut down the production.

Bay said he first found out about the injury from CNN online and did not believe it was true. Producer Ian Bryce confirmed it and wanted to close up shop to accommodate LaBeouf's recovery. Bay knew it would be too expensive to shut down and thought of a way to work around the hand.

The scene on the schedule for the next day was a library action sequence. Bay shot as much as he could with LaBeouf's stuntman. Then, while Bay figured out what shots he could fake with the double, he ordered a top-of-the-line cast made for his leading man. LaBeouf's film cast included Kevlar fingers so thin they would photograph as skin.

"The problem was if he were to jam his fingers he could lose his fingers forever," Bay said. LaBeouf broke two fingers of his left hand.

The film was halfway into production when the injury happened, so the bulk of earlier scenes had been completed. For the latter part of the film, the filmmakers easily wrote an old-school white cast into the Egyptian climax. Sam Witwicky (LaBeouf) suffers a teleportation injury when he lands on his hand in the desert and gets a cast to wear for the rest of the film.

Co-star Megan Fox also gave LaBeouf props for showing up to work with the injury, even trying to do dangerous stunts for the sake of realism. That inspired her to step up her stunt game, she said.

But Bay made sure to err on the side of caution. When LaBeouf offered to take his cast off, Bay insisted he put it back on. "We were just trying to protect the hand," he said.

Transformers: Revenge of the Fallen opens Wednesday.

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