“LU OVER THE WALL”

**

(PG, 1:52)

Building walls between cultures is never a good idea; so says the Japanese anime “Lu Over the Wall.”

In the case of the small coastal town of Hinoshi — a place where dreams go to die — the inhabitants of the fishing village are on one side, and the merfolk — yes, mermaids and mermen — are on the other. The merfolk have caused numerous shipwrecks and killed several villagers, the town citizens claim, so after the construction of a sea wall ages ago, the merfolk have not been seen in decades.

That is, until a fish-out-of water teenage human named Kai starts a band, and a discovers a childlike mermaid who loves to dance. Can music finally bring these two cultures together?

Kids will enjoy this loopy adventure most, although director Masaaki Yuasa might tax even their patience by fitting about 80 minutes worth of storyline into 1 hour, 52 minutes. A film with a case of the cutes, there are visual references to “The Little Mermaid,” “The Creature from the Black Lagoon,” “Footloose,” “Josie and the Pussycats” and even “Cocoon” to keep the adults interested.

Kai is a moody kid who has just moved to Hanishi from Tokyo. He creates music electronically and makes videos, posting them on YouTube anonymously. (His dad and grandfather might disapprove.) When classmates Yuho — a pretty girl with a crush on the moping Kai, who often keeps his head low and cap pulled down — and cool guy Kunio discover the videos are his, they urge him to form a band with them.

It takes some time, but Kai finally agrees, though a frown remains his go-to expression. Kai is playing music when Lu, the mermaid, makes her first appearance, tapping her fins along with the beat. She enters the room by hovering near the ceiling in her own bubble while Kai, on the floor, stays dry.

It’s the relentlessly positive Lu who brings Kai out of his shell. “Sounds like you like everything,” Kai tells Lu. “I don’t like anything. I haven’t for a long time.”

Soon, Lu becomes not only the band’s mascot, but an important guide to the band’s rhythm.

At first, Lu is their secret. And she begins to show her new human friends some of hers. Like the neat way she can make a cube of water float like Aladdin’s magic carpet, over towns and cities. At one point, they are literally chasing rainbows.

The band gets their first gig — a yearly festival that honors the townsfolk lost at sea. Not the greatest place for Lu’s coming-out party, and her appearance causes an uproar. Soon, the town council is organizing a plan to keep the merfolk in their place, but when disaster threatens, will the merfolk use their special powers to help the town that shuns them?

“Lu Over the Wall” is not bad, mostly charming, though Kai’s mopefest gets a little tiresome and there’s a nonsensical subplot involving Yuho that is a distraction.

It’s colorful and imaginative, but other than Lu, the characters don’t have much depth. Emotional, that is, not oceanographic.