Swiss car modification firm Rinspeed has built the world's first real submersible car inspired by the James Bond film The Spy Who Loved Me.

Unveiled at the Geneva Motor Show, the sQuba concept car is a zero emission vehicle driven entirely by electric motors.

Rinspeed boss and James Bond enthusiast Frank Rinderknecht said: "For three decades I have tried to imagine how it might be possible to build a car that can 'fly' underwater. Now we have made this dream come true."

The sQuba's ability to undertake submerged stable flight at a depth of 10 metres sets it apart from currently available military vehicles which can travel under water but are limited to driving slowly over the submerged ground.

"It is not easy to make a car watertight and pressure resistant enough to be manoeuvrable under water. But the real challenge was to create a submersible car that moves like a fish in water," explained Rinderknecht.

The sQuba is driven by three electric motors located in the rear, one providing propulsion on land and two driving the propellors for underwater motoring.

However, unlike the car that inspired it, the sQuba will not keep the driver or passengers dry during the underwater jaunt.

The car floats when it first enters the water, and begins to sink only when a door is opened to let water in. The vehicle has an integrated tank of compressed air, and breathing apparatus built into the dashboard.

"For safety reasons we have built the vehicle as an open car so that the occupants can get out quickly in an emergency. Opening the door with an enclosed cabin might be impossible," explained Rinderknecht.

Buoyancy issues also dictated that the car had to have an open-top design. An enclosed volume of just two cubic metres of air means that the vehicle's weight would have to increase by two tons to counteract the unwanted buoyancy.

As an added safety measure, the sQuba surfaces automatically if the occupants leave the car.

The sQuba is expected to cost in the region of £750,000.