It's tempting to like Percy Jackson: Sea of Monsters for what it is not. For example, it is not a movie where anyone shouts, "LET'S DO THIS!" (which, along with its dim-witted cousin, "LET'S FINISH THIS!" is the most ubiquitous bit of gung-ho verbal nothingness to appear in blockbuster-minded scripts all summer long, and I know this because I write it down in my little notebook at least once per press screening, twice during The Smurfs 2 -- it's already 2013's "You just don't get it, do you?")
It's also tempting to like Percy Jackson: Sea of Monsters simply because it tries so hard. It knows its debt to everything Harry Potter already accomplished and it's content to live in that shadow, aiming for a somewhat younger audience demo and holding way back on terrifying darkness, bloodshed and death. In its own way it acts as training wheels for future Potter consumption while spoon-feeding its young fans rudimentary knowledge of Greek mythology.
But the best reason to (mostly) like this second chapter in the saga of a teen demigod (Logan Lerman), the half-blood son of Poseidon, is that it's clear and uncomplicated, it hits its marks like it should and provides enough derivative spectacle to please its tween fans, most of whom haven't seen enough of this sort of thing to know it's all been done before.
Percy has to retrieve the Golden Fleece from the Sea of Monsters in order to repair the broken barrier set up around the demigod training camp he's attending with the children of other gods. The path to this is fraught with obstacle, almost-danger, fire-snouted mecha-bulls, eyeless witches driving mystical taxicabs, Nathan Fillion as Hermes posing as a quippy UPS guy, ocean vortexes smack dab in the middle of the Bermuda Triangle that swallow Percy and his pals into a giant underwater digestive tract and an abandoned island with a crumbling amusement park presided over by a hungry cyclops. If none of those stations of the cross (sorry, mixing up gods, I know) sound like they possess any sort of organic flow, well, they don't. Episodic, random and lacking any one set piece that stands out as more memorable or exciting than the others, it displays all the narrative qualities of a story made up by a child babbling in the backseat on his way home from the dentist.
That this isn't such a horrible experience to sit through comes down to the way that the whole of it is dead set on believing its own line of goofy reasoning. And Lerman, though 21 and appearing all of 14, the kind of young man who'll be carded in bars until he's 40, is a wide-eyed avatar for 9-year-olds who know they wouldn't have the gravitas to deal with a Voldemort-level threat, but who'd be perfectly willing to try outracing a digital cyclops on a runaway roller coaster. Sometimes that's enough.