A five-knot top speed makes this the slowest Aston Martin ever, but this super-cool sub has plenty more to offer

Built by Triton Submarines rather than the Aston Martin factory at Gaydon, Project Neptune is a personal submarine that was developed in conjunction with Red Bull Advanced Technologies, who also developed the Aston Martin Valkyrie ‘hypercar’.

Improved hydrodynamic efficiency, reduced frontal area, and increased power give an anticipated ‘sprint’ speed in excess of five knots and approximately four times the acceleration of Triton’s current flagship 3300/3 model.

According to John Ramsay, chief technical officer at Triton Submarines, “The interior is quintessentially Aston Martin — a luxurious mix of hand-stitched leather and high-performance carbon-fibre.”

There are three Designer Specifications to choose from, and “Customisation and personalisation options will be available courtesy of Aston Martin’s bespoke service, Q by Aston Martin.”

The base price is $4 million from Triton Submarines or your local Aston Martin dealer.