Madison, 29, looked quite the mermaid as she displayed her twin assets during the underwater pose, reports the Sun.
The busty Playboy blonde, a former girlfriend of Hugh Hefner, did the X-rated underwater display as she posed for a kinky shoot.
She could be seen resting seductively on the seabed before popping out of the water for a shot of her famous chest.
Madison also flashed her bum as she leaned over a giant rock. (ANI)