There’s an inviolable law of animated films — the more “names” you have in the voice cast, the weaker you know your film is.

Aardman, those metiulous Brits who build clay models and painstakingly animate them into Wallace & Gromit cartoons, and the hit “Chicken Run,” tip their hand that way with “The Pirates! Band of Misfits.” A pirate picture that’s entirely too late to the party to have much in the line of fresh gags, it is stuffed with name actors, from Hugh Grant as The Pirate Captain to Salma Hayek, Brendan Gleeson, Imelda Stanton, Anton Yelchin and Jeremy Piven.

And all of them sat in a recording booth and struggled to find funny things to say or funny ways to say the not-so-funny things in the script. Amusing in small doses, here and there, “Pirates” is the first Aardman film to suffer a serious shortage of sight gags, the first where the whimsy feels forced and the strain shows.

Hugh Grant’s Pirate Captain (That’s his name) is all Hugh Grant stutter and “glittering eyes and glorious beard.” As a pirate, he’s something of a bust, even though his crew adores him. He figures he’s due for the “Pirate of the Year” awards. But he’s always come up seriously short in the pirate booty department. There’s always a Cutlass Liz (Salma Hayek), Peg Leg Hastings (Lenny Henry) or Black Bellamy (Jeremy Piven) to beat him to the podium.

And so it appears it will be in the 1837 awards, until he stumbles into Charles Darwin (Martin Freeman), a scientist who craves fame as much as The Pirate Captain. And Darwin recognizes the Captain’s pet “parrot,” Polly, as something altogether more amazing. She’s the last Dodo bird.

He talks The Pirate Captain into sailing to Britain, under the nose of pirate-hating Queen Victoria (Imelda Stanton), where Darwin hopes to present the bird to The Royal Society, whose entryway is marked “Playing God since 1807.”

So you’ve got pirates roughly 120 years after their heyday, and a scheming Darwin, with his evolved chimp pal, a “Man Pan Zee,” he calls him. You’ve got other scientists, hoping to win acclaim with everything from airships to a Rubik’s Cube. You have competing pirates, all swagger and swordplay.

What you don’t have is a lot of laughs. Backing the ship up, we hear the “beep beep beeps” of every modern minivan. There are hints passed from pirate to Darwin about evolution, which he never picks up on. The Pirate Captain attacks all manner of unlucrative prey — a ghost ship, a school “field trip” ship, a plague ship (changed from a leper ship after leprosy-advocacy groups complained).

Most of which amount to a grin, a chuckle. Those of us who love Aardman will appreciate the gorgeous attention to detail, made sharper (not much sharper) by 3D.

But “Pirates” plays like a fussy film made by fussy little fussbudgets, clever chaps all wrapped up with making perfect plasticene trees, but who lose track of the forest — the funny movie that is supposed to be animated around this detail. Where’s the invention of “Wallace & Gromit,” the genre-goofing glee of “Chicken Run”? 

Fans know that the weakest Aardman films (“Flushed Away” wasn’t a laugh riot either) are still richer and more rewarding than any “Shrek,” “Cars” or “Ice Age” picture.

But as long as these films take, as expensive as they are to do, it’s almost tragic when they spend their efforts rounding up big name misfits, and then give them so little mischief to get into.

MPAA Rating:PG for mild action, rude humor and some language

Cast: The voices of Hugh Grant, Salma Hayek, Jeremy Piven, Martin Freeman, Anton Yelchin and Brendan Gleeson.

Credits: Directed by Peter Lord and Jeff Newitt, screenplay by Gideon Dafoe, based on his book. An Aardman/Sony Pictures Animation release.

Running time: 1:28