This is the big kahuna of big-animal night dives. There are plenty of blue spots around the planet where you can interact with mantas during the day, but only off Kona, Hawaii, can you commune with these magical flying carpets after the sun goes down.
If you only do one night dive in your life, this should be it.
Almost every dive shop in Kona includes this dive on their menu. It's one of the most surreal and thrilling encounters under the sea.
Here are the nuts and bolts:
A big two-headed light is placed on the seafloor aiming straight up toward the surface. This attracts zooplankton by the zillions. Mantas feed on this tiny marine vittle. Mantas aren't dumb, and the local population has learned to see the lights as a dinner bell. And where there's an abundant source of easy pickin's and the creatures that feed on them, you'll find divers. 'Cuz divers aren't dumb either.
This is also one of the easiest dives you'll ever do. Your only requirement is to kneel on the rubble at 40 feet and take in the bizarre scene. Sometimes up to seven giant mantas show up and swoop in tight loops above the lights, straining as much of the wriggling little critters as they can. They'll remain all night, as long as the lights attract food. They'll come in close if you hold up your flashlight giving you the ultimate eye-to-eye how-de-do. Sometimes they'll come in straight at you on strafing runs, with their mouths agape so you can see right down their throats, looking like they might engulf you in their cephalic fins as they maneuver just inches above your head. With so many lights stabbing the night sea, the scene is reminiscent of the Close Encounters finale. But this scene does not exist in a fictional imagination. It's just one more patently unforgettable experience that makes diving the coolest sport on the planet.