It’s hard to know where to begin describing The Pirates! Band of Misfits, just because of how extraordinarily silly it is. How silly is it? The main characters are never given names. The film follows a pirate captain who’s only ever referred to as Pirate Captain. That’s seriously his name. By the same token, the first mate is known exclusively as “Number Two.” There’s also a female pirate in their crew who’s obviously and transparently disguised as a man, but they just call her “The Surprisingly Curvaceous Pirate.” That’s the only name she gets in the film, and everybody is totally oblivious to the fact that she’s so clearly a woman. That’s the joke.

It should be obvious very early in the proceedings that this movie works entirely on its own demented form of logic. This isn’t just a silly movie, it’s a movie that knows exactly how silly it is and positively revels in it. Yet the characters play all the self-referential humor completely straight, which actually makes it funny.

It’s a time-tested approach to comedy, though it only tends to work if there’s some baseline of normalcy to contrast the weirdness against. The film provides two such sounding boards. One of them is Number Two — voiced by Martin Freeman — who’s probably the only member of the crew without any quirks at all. He’s effectively the crew’s moral compass and voice of reason, not that his guidance is heeded 100 percent of the time.

The other source of normalcy is provided by the Pirate Captain himself (voiced by Hugh Grant). It’s established early on that he’s a devoted Pirate Captain with a loyal crew, despite the fact that they’re all horrible fuckups. Here’s a guy who tries his absolute hardest to get some measure of appreciation from his peers, only to fail repeatedly and get ridiculed on a constant basis. Even if the Pirate Captain is a total idiot who acts in outlandish ways, the character — and also the story — are given a perfectly relateable foundation for us to latch onto. Of course, the Pirate Captain is so pathetically inept and his rivals are badass to such a ridiculous degree (one of them rides a sperm whale into a bar, for Neptune’s sake) that the contrast is hilarious in execution.

Through the first half hour of the movie or so, everything’s going great. We meet the Pirate Captain and his crew. We meet the psychopathic Queen Victoria, voiced by Imelda Staunton in a performance that makes Dolores Umbridge look well-adjusted. We get a few laughs courtesy of Pirate Captain’s rivals (voiced by Jeremy Piven, Salma Hayek, and Lenny Henry) as well as their competition for the coveted “Pirate of the Year Award.” We also get a sequence to show the Pirate Captain’s repeated failures at pulling off a raid.

The whole first act is a bunch of over-the-top fun. Then it ends and we’re introduced to Charles Darwin. Yes, that Charles Darwin.

See, the pirate crew unknowingly raids the friggin’ HMS Beagle and they run into Charles Darwin, who discovers that Pirate Captain’s parrot is actually the last dodo in existence. Darwin then convinces the pirate crew to take the dodo to London, where Darwin can present it to the scientific community for a huge prize. Part of the prize is an audience with the aforementioned psychotic queen, whom Darwin has a crush on.

Okay, one: Wasn’t this supposed to be a pirate movie? You know, high seas adventure, ship battles, raiding gold, all that good stuff? When the hell did this turn into “adventures in the London scientific community?”

Two: Whose bright idea was it to make the parrot into the movie’s MacGuffin? Again, this is a pirate movie! Why couldn’t it have been some kind of treasure?

Three: What in the name of Watson and Crick is Charles Darwin doing in this picture?! Why on Earth did the filmmakers put an actual historical figure into a movie so blatantly and proudly removed from reality? For that matter, why did the filmmakers take one of the most revered figures in science and turn him into a villain? Hell, he isn’t even a villain in the picture so much as he’s a spineless toady obsessed with finding a girlfriend! This character has absolutely nothing to do with the real Charles Darwin, so why put his name in there at all? They could have and should have just invented an original scientist character out of whole cloth and it would have done the film far more good.

If it sounds like I’m blowing this out of proportion, keep in mind that Darwin gets a TON of screen time in this movie. He pretty much singlehandedly drives the entire second act, and he plays a crucial role in the third act as well. Again, the question must be asked: What place does this have in a pirate movie?

You’d think that the rival pirates would be the antagonists of the picture, but that would’ve made too much sense. Jeremy Piven’s character kicks off the third act, but that’s the only effect he has on the plot. Salma Hayek basically gets a glorified cameo and Lenny Henry’s part could have been cut from the film entirely.

That said, at least the voice acting is great across the board. Hugh Grant, Martin Freeman, Imelda Staunton, David Tennant, Brendan Gleeson, and Anton Yelchin all completely disappear into their characters, to wonderful results. Brian Blessed even appears for a scene, and it’s always an amazing thing to hear him give a voice performance.

I should also add that the animation looks sublime from start to finish. In particular, the water effects are so impressive that I’m sure it was done with CGI. Either that or the stop-motion animators at Aardman are impossibly good. I’ll accept either explanation. As for the 3D, this movie is filled to the brim with shots of swords, cannonballs, goofy spring eyeglasses, and other objects flying toward the camera. So basically, the 3D is every bit as conspicuous, gimmicky, and goofy as the film’s humor.

I also hasten to add that when the film finally gets to the climax, it’s very good. The final battle of the film offered precisely the kind of wacky, heightened, implausible high-seas spectacle that was promised by the first act. It’s just a damn shame that we had to go through the second act to get to it.

The Pirates! Band of Misfits could easily have been a good movie. As it is, the film already has a lot of effective humor, solid voice acting, and wonderful animation throughout. Alas, the film has a horrible second act that squanders the promise of the first. Despite the entertaining climax, this film completely jumped the shark (aquatic pun!) when the filmmakers decided to make Charles Freaking Darwin the antagonist instead of, you know, PIRATES.

I can recommend this movie for a rental, but it has no business competing for your box office dollars this summer.