At a time when the smallest on-set squabbles get immediately YouTubed out of proportion, here’s one that might make even Christian Bale and Werner Herzog take note: During the filming of the prequel to 2003’s Thai martial-arts classic Ong Bak, stressed-out star/director Tony Jaa vanished into the jungle, disappearing for two solid months before tearfully reappearing on a talk show with a newfound resolution to kick ass. The resulting film may not quite live up to that backstory—to be honest, not much could—but that’s not to say that it ever falters in its dedication: Ten minutes in, someone’s already been basted in blood and thrown into a pit with a real live crocodile. Things build from there.

Set in 1421, and bearing only the slightest connection to the original film, the story follows the saga of Tien, an orphaned son of a nobleman who undergoes a series of deadly tests in order to fulfill his destiny as king of the pirates. Should you be burned out on the whole Joseph Campbell hero thing, be advised that said tests include swordfights, duking it out with a voracious vampire woman, and punching an elephant.

Amid all of the radness, there are problems: The epic historical setting, however sumptuous, loses much of the DIY Jackass quality that gave the original such a quasi-snuff-film feel, while the cliffhanger ending is a botch that the genius internet critic Vern (www.outlawvern.com/2009/05/01/ong-bak-2) has already compared to Tinkerbell clapping. That said, if you have even the slightest interest in action movies, this is a must-see, especially when it comes to the head-thumping nirvana of the incredible last half-hour, as Jaa takes on an increasingly absurd legion of bad guys without ever stopping to take a freaking breath. By the time a dude in a bird suit starts fighting on top of a moving elephant, it seems like a logical, completely awesome progression. Shine on, you crazy diamond.