This was enough for me, but the fighting was as clumsy as it was unimpressive. The sappy nod to ADD and Dyslexia was lame in the extreme as was the 'oh I'm only faking having palsy in my legs to protect you Percy' routine of his sidekick. Puh-leeze.
The dramatic moment when the lead's mother is killed is botched so badly I was agape. Not a moment was spared to mourn her death. It was basically, "Oh wow you're moms is croaked, bummer dude...but hey let's go LARP!". So to confirm the last poster's suspicions: FAIL. Uma as Medusa, worth it. The sort-of romantic interest is a fizzle, and poorly acted by some forgettable person with breasts, which is all you'll remember about her. Some glam-rock throwback as Hades, FAIL. Olympus is in the Empire State Bldg. and all the gods argue in English-? FAIL. In fact, the whole plot is a FAIL. But Charon was well played, even though they borrowed Hell from Constantine.
Watchable, barely.