What right does "Dredd" have to be so awesomely entertaining?

For one, the film is a remake of a silly 1995 Sylvester Stallone comic book adaptation, and as we all know, remakes are Hollywood's visual representation of a smug, half-hearted shrug. It's directed by Pete Travis, the guy behind the instantly forgettable "Vantage Point," in godforsaken 3-D. Worst of all, "Dredd"'s plot – cops trapped in an apartment complex of guns, gangsters and doom – was effectively used already this year in the underground action hit, "The Raid: Redemption."

Yet somehow, despite all of that going against it, "Dredd" ends up being one of the most vigorously entertaining movies of the year so far and one of the best glorified B-movies to come since my cherished "Piranha 3D." Talk about defying expectations.

"Star Trek"'s Karl Urban plays Judge Dredd, a street cop who keeps order in the futuristic dystopia of Mega City One by being judge, jury and executioner. While training a new recruit with psychic abilities (Olivia Thirlby, Ellen Page's BFF in "Juno"), Dredd runs across a strange murder in a massive slum/apartment complex called Peach Trees.

The murder turns out to be linked to Ma-Ma ("300"'s Lena Headey), a sadistic drug dealer who's dealing a new brand of narcotic called Slo-Mo, which does exactly what you think it does. When Dredd and his recruit get too close to the truth, Ma-Ma locks down the complex and puts a bounty on the two judges, who must now shoot their way to freedom.

And boy do they shoot their way to freedom. "Dredd" could easily be the most violent movie of the year. Limbs explode, flares and bullets are fired (most of the time in glorious, over-saturated Slo-Mo induced slow motion) and people are dropped to their death from more than a hundred stories up. One character even bloodily plummets right onto the camera in eye-popping 3-D.

It's a grimy, gritty and often gaudy apocalyptic atmosphere – the Slo-Mo sequences, with their overly bright colors combined with the dreamy bloom effect, look almost sickly, like a watercolor nightmare. An early mall gunfight ends with blood and bodies getting clumsily cleaned up, a morbidly normal part of everyday life in Dredd's world.

Thankfully, the grim environment never suffocates the giddy B-movie fun "Dredd" hopes to provide. Travis' direction, combined with Alex Garland's screenplay, hits the perfect grindhouse tone of fun, bloody mayhem that never allows it to get too bogged down in seriousness. There are a few moments when the story slows down a bit, but an outrageous action scene is never too far away.

While its gory gunplay may not match the brutal ballet that is "The Raid: Redemption," "Dredd" contains two elements its Indonesian counterpart was utterly devoid of: story and characters. Garland (the writer behind "Sunshine" and "28 Days Later") doesn't reinvent much, but he knows how to keep the story moving in exciting directions. The movie doesn't feel like a video game, with Dredd and his protégé defeating each level of the complex; instead, it's a futuristic "Die Hard"-esque game of cat and mouse (if animals could use machine guns).

Garland's characters are fun to follow as well. Urban plays Dredd with a cold, growly voice (think Bale's Batman voice but far more natural) and a permanent scowl. Dredd is seemingly an emotional brick of a man, but Urban finds a way to give him nuance and make him still likeable. We want him to succeed and survive because we like him, not just because he's the main character.

Thirlby is better than the usual inexperienced partner character as well. As goofy as her character's psychic abilities are (I chuckled when they were first mentioned), they create intriguing dynamics for the character, especially her mental battles with Ma-Ma's most trusted underling, played by Wood Harris from "The Wire."

I know it may be strange to talk so much about story and characters in an unapologetic action B-movie when there are awesome explosions, gunfights and one-liners to drool over. Even the most testosterone-packed action sequences, however, can cause the audience's eyes to glaze over if there's no reason to care about who's shooting at what and why.

"Dredd" provides just enough to get the viewer involved and then satisfyingly delivers the genre pleasures that action fans crave. And they've been craving them for a while. Sure, there have been a lot of attempts, like "Lockout" (too dumb), "Machete" (too message-heavy) and "Hobo with a Shotgun (too ugly). But "Dredd" is the first B-movie in a while in which the B stands for badass.