Movie memorabilia can collect some steep premiums, so when a mystery buyer shelled out close to $1 million for the Lotus-based submarine from the 1970s-era James Bond film, “The Spy Who Loved Me” few were surprised.

The real shocker turned out to be who bought that movie prop – and why. Tesla Motors CEO Elon Musk snapped up the Lotus body for $989,000 at an RM Auction in London last month. Further, Musk says he plans to turn the prop into a working sub car, using a Tesla electric drivetrain.

"It was amazing as a little kid in South Africa to watch James Bond in 'The Spy Who Loved Me' drive his Lotus Esprit off a pier, press a button and have it transform into a submarine underwater," Musk confirmed in an e-mail to NBC News. "I was disappointed to learn that it can't actually transform. What I'm going to do is upgrade it with a Tesla electric powertrain and try to make it transform for real."

The Lotus Esprit was driven by Roger Moore, the British actor who followed original James Bond Sean Connery into the 007 role for a number of ‘70s-era thrillers. With the prerequisite Bond girl at his side, the super spy evades an attacking helicopter by plunging his car off a pier. The wheels retract, fins emerge and with the touch of another button, a rocket launches, blasting the chopper from the sky.

There were several different Lotus sports cars used in the film, each modified for a specific shot, such as deploying the fins. The actual Esprit submarine, which was sold at auction to Musk, was a prop body operated by a stunt man wearing scuba gear.

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Musk hasn’t said, yet, what his exact plans are – for example, whether it will be able to drive on land and then convert to a true submarine – nor whether he plans to show off the final version by personally driving off a pier.

One thing is clear, despite some clear eccentricities, Musk backs his plans up with cash – lots of it.

Originally making a fortune on the Internet financial service PayPal, he has since branched into a variety of different fields. In the automotive world, he is probably best known as the founder and CEO of upstart battery-carmaker Tesla Motors, whose Model S sedan has become one of the market’s few battery-electric success stories.

Musk also founded Space Exploration Technologies Corp., or SpaceX, a California-based private rocket service that has a major contract to run supply ships to the International Space Station. SpaceX is currently developing a manned rocket that would take over American astronaut launch duties from the Russians.

Musk is also dabbling in solar power and has even proposed a novel alternative to high-speed rail in which passengers would be launched at nearly the speed of sound in low-pressure tubes connecting major cities such as Los Angeles and San Francisco.

By comparison, it might seem, transforming a movie prop into a working sub/car might seem easy.

There are, incidentally, several car-to-boat projects underway, and those with serious wealth now can buy their own submarines. But transforming a car into a sub at the touch of a button would be something worthy of Q Branch if Musk can pull it off.

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