Are the parents sitting on the MPAA's ratings board out of their minds?

This is not a rhetorical question, because the answer is "Yes, they are" if they honestly believe that the stab 'em, rip 'em, slice 'em, dice 'em, martial arts exploitation action film "Ninja Assassin" doesn't qualify as an adults-only movie.

In the opening sequence of James McTeigue's high-velocity, gleefully gory experience, a ninja assassin wipes out a room full of scoffing ruffians. Heads explode in crimson showers. Body parts fall to the floor. It takes one man a few seconds before he realizes he's been neatly sliced in half, the long way. One half of him can only watch in horror as his other half slides to the floor.

"Ninja Assassin" isn't just one constant blood geyser. It's the Old Faithful of blood geysers.

That "Ninja Assassin" would merit a mere R rating shows just how the MPAA's Ratings Board has abandoned its responsibility to properly advise and warn American parents about the increasingly frank and explicit nature of today's movies.

There's nothing wrong with the violence per se in the spectacularly crimson "Ninja Assassin," which closely approximates the kinetic, pseudo-realism of an ultraviolent video game.

Korean pop star Rain brings agility, tight muscles and a Bruce Lee-like intensity to his role as Raizo. He's a rogue ninja who goes against the secret society of assassins who raised him so that he can protect attractive Europol agent Mika Coretti (Naomie Harris, the only cast member who displays talent for acting).

Mika discovers the existence of the Nine Clans, ancient sects of killers for hire, and now they intend to silence her. The only thing slowing down Raizo are his frequent flashbacks, when he remembers his harsh ninja training and the one ninja girl who loved him more than killing strangers.

The dialogue, embarrassing verbiage with hokey hooks such as "She has a special heart," was so arch that a hard-core action audience Monday night loudly guffawed and hooted at it.

Nobody goes to see "Ninja Assassin" for crisp dialogue and believable character development, anyway.

This is a movie designed for young people who haven't experienced true violence and horror in their lives, and can still get a buzz from the graphic nature of the "quality kills" in this no-holds-barred action film.

Apparently, the people sitting on the Ratings Board did.