The Submarine Car (nicknamed "Wet Nellie") was built by Perry Oceanographics (they made the motor) with the assistance of production designer Ken Adams and special effects supervisor Derek Meddings (who modified the shell).

The Lotus sported tires that disappeared inside the body, air- tight wheel arches the covered the tires, moveable wing blades protruding over the wheel wells that allowed the car to bank, dive and climb like an airplane, and louvered pressurized windows.

Its gadgets included rear firing mud sprayers, limpet mine depth charges, surface-to-air missiles, underwater smoke screens, and torpedoes.

In reality, the movie car actually didn't operate as seen. Two skin divers with Aqua-lungs sat inside the vehicle as it moved along the bottom of the crystal-clear waters of the Bahamas where the scenes were shot.

The original idea of having a dry interior was deep-sixed when problems with air and ballast affected the design. Rear license plate reads: PPW-306R. Front license reads: ESPRIT. 

TRIVIA NOTE: In December of 2008, the classic white 1976 Lotus Esprit sports car driven by Roger Moore (on land and under water in the 1977 Bond film The Spy Who Loved Me was sold by Bonhams auctioneers in London for £111,500 ($262,000). The car was purchased (via telephone) by a private collector with ties to Atlanta, Georgia.