The lights are first visible just under the water. At first glance, you think they may be nothing more than reflections, perhaps some strange refraction of the moon overhead. And then the lights move with a life of their own, bursting out from beneath the surface of the river and rocketing like missiles toward the sky.

It sounds like a scene from some fantasy novel, but if you happen to be walking along the banks of the Mekong River in Thailand during the month of October, you may very well see this puzzling sight. The lights are attributed to the Mekong Dragon, a supernatural spirit of the river who governs the water flowing there. The Thai people propitiate this ancient being with a festival of lights. Dragon boats are raced upon the river, and human-made fireballs are launched into the sky in the form of cunningly crafted fireworks. But all of this pales to the amazing sight of the fireballs themselves, which emerge from the depths of the river and blaze forth in the night.

Are the lights man-made hoaxes? Perhaps they're merely swamp gas — although they would have to originate from some well-timed emissions, since the lights only emerge from the river during the time of the annual festival. Certainly, some strange things have come out of the Mekong River. Given the 646 pound catfish caught in 2005, the idea of a dragon lurking beneath those same waters becomes suddenly far more credible. Giant catfish aside, the river-born fireballs remain a mystery. While skeptics ponder, the Thai people engage in their lively festival, mingling Buddhist and animist beliefs in a richly textured worldview that leaves plenty of room for dragons.