Three years after Percy Jackson’s last adventure against the Lightning Thief, our now much older demigod returns in a film most moviegoers were likely indifferent about, considering how few filled the seats for the first installment. But just like any good underdog, Percy (Logan Lerman) finds his way back to the big screen, and he does so in a film that isn’t completely terrible. We’ll call that a win of sorts.

Tyson (left), Clarisse, Grover and Annabeth join Percy Jackson in the new film based on the mythical Greek gods. (photo courtesy of Fox Pictures)

In the incapable hands of director Chris Columbus, the first film spent so much time establishing the world of half-bloods — the children of Greek gods in an outdoorsy Hogwarts — that the intrigue of Rick Riordan’s “Olympians” book series remained absent. In a somewhat corrective way, “Percy Jackson: Sea of Monsters” (note the shortened title to avoid ridiculous wordiness) establishes the series’ overarching storyline, the gods’ father Kronos’ rise from the underworld. Gods hater No. 1, Hermes’ son Luke (that darned Lighting Thief from the first film, played by Jake Abel), leads the charge by attacking the barrier protecting Camp Half-Blood.

To save the camp, Mr. D (god of wine Dionysus, played by always delightful Stanley Tucci) comes up with an original plan he learned from Annabeth (daughter of Athena, played by Alexandra Daddario) to locate the Golden Fleece to heal the great pine tree made from Zeus’ dying daughter, Thalia, that protects the camp (it’s a whole backstory thing, just watch the movie if you want to know more).

While Mr. D chooses Ares’ daughter, Clarisse (Leven Rambin), to embark on the quest, Percy learns of a prophecy that leads him to believe his destiny resides with that fleece. So with the help of love interest Annabeth (I know, they’re technically related since his father Poseidon is uncle to Athena), his trusty satyr Grover (Brandon T. Jackson) and newfound cyclopes half-brother Tyson (Douglas Smith), they begin their trek to the Sea of Monsters –– what we know as the Bermuda Triangle.

If nothing else, at least “Sea of Monsters” manages to be fun despite Marc Guggenheim’s lazy screenplay. He clearly knows his way around TV series (“Arrow” and “Eli Stone” in particular), but someone at Fox, or director Thor Freudenthal (“Diary of a Wimpy Kid” and “Hotel for Dogs”), were probably OK with a mediocre first draft. After all, a children’s film doesn’t need to have subtext or layered characters –– save all those pesky Harry Potters and the most successful Pixar films.

I often wonder why filmmakers green light shoddy writing, moving forward with something bland when memorable is so close. The gods know this is a fantastic concept based on a popular book series; if only someone could give Greek mythology the 15 minutes (fine, fine, two hours plus) of cinematic fame it deserves.

Writing aside, the film manages moments of actual fun, more so than a few undead and mutant installments this summer that received far more praise than they deserve. What it lacks in humor and performances, it makes up for in choice visual effects (trust me, though, not all of them work). The action-packed scenes that don’t overdo it (until the end) are decent. That’s the new seal of approval amid several other cinematic yawners of the past few years.

Logan Lerman portrays Percy Jackson (left), Alexandra Daddario appears as Annabeth and Douglas Smith stars as Tyson in “Percy Jackson: Sea of Monsters”. (photo courtesy of Fox Pictures)

I must applaud a prominent revision to the book. Tyson is far more stupid on page, channeling Jar Jar Binks instead of Hagrid and other lovable oafs. Luckily, Tyson isn’t an idiot, just clumsy and naive, even managing a few witty lines of banter. Even Leven Rambin, as hotheaded Clarisse, overshadows our series regulars, making me sad for the next films. But none compare to Nathan Fillion’s brief but sensational appearance as Hermes, messenger god of Olympus. He might look like a UPS employee to all you normal people, but behind the scenes, he’s just as charming as he is well dressed.

Sure, there have been several better films at the box office — even recently — but “Sea of Monsters” provides enough distraction to make the film survivable for a single viewing. Hopefully they’ll improve a little bit more if a third film goes forward. Perhaps by the time the fifth film (and maybe even the spinoff series) rolls around, something akin to actual quality will materialize that deserves a greater compliment than “not bad.”