In The Spy Who Loved Me, James Bond drives a Lotus Esprit that transforms into a submarine.
Bond receives the white Lotus from Q branch and uses it during the Sardinian pursuit. After entering the water, the car changes into an amphibious submarine with fins, ballast equipment and underwater weapons, allowing Bond and Anya Amasova to escape their pursuers.
The transformation is fictional, but the Lotus Esprit itself was a real mid-engined sports car designed by Giorgetto Giugiaro. Its sharp wedge shape made it particularly effective as a futuristic-looking Bond vehicle.
The car is often called simply the “submarine Lotus,” but the precise model is the Esprit. It is not the Lotus Europa, Elan or later Excel, all of which were separate Lotus models.