Inside Wealth

Tesla's Elon Musk wants to make sub car a reality

Elon Musk goes 007!

Movie memorabilia can collect some steep premiums these days, so few were surprised 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."

But the real surprise turns out to be who bought that movie prop—and why. Turns out it was Tesla Motors CEO Elon Musk who snapped up the Lotus body for $989,000 at RM Auctions in London last month. As to why? Musk has confirmed plans to actually turn the prop into a real, working sub car. And, in case you haven't already guessed, his goal is to use a Tesla electric drivetrain.

James Bond's underwater Lotus from the "Spy Who Loved Me".
Source: RM Auctions

(Read more: How James Bond's submarine car was discovered in Long Island)

"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 said in an emailed statement. "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.

'Bond-mobile' goes to auction

With the prerequisite Bond girl alongside, 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.

In fact, 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 was a prop body that was operated by a stunt man wearing scuba gear. It was that version sold by RM Auctions to Musk.

(Read more: James Bond submarine car fails to wow at auction)

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 eccentricities, Musk backs his plans up with cash—lots of it.

Originally making a fortune from 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, 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.

(Read more: How to be cool like James Bond)

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.

By CNBC Contributor Paul A. Eisenstein. Follow him on Twitter @DetroitBureau or at