The villain is often the best thing about a story, and the cute idea of the original “Despicable Me” was that the villain would be the main character.

This was Gru, the bald evil genius who tried to steal the moon. Not only did the 2010 animated film make a bundle of money, so did its sequel and spin-off (“Minions,” devoted to Gru’s small, yellow, chattering assistants).

The thing is, the villain is still the best thing about “Despicable Me 3.” That’s a problem, because Gru is a good guy now.

An uninspired sequel by any standard — except, to be fair, maybe a 5-year-old’s — “Despicable Me 3” feels like three different ideas patched together and played out in disconnected skits.

Gru (voiced again by Steve Carell) has his three adopted daughters and the wife (Kristen Wiig) he picked up in the previous films. The family twist here is that Gru has a twin brother, Dru, who has fewer brains and more hair (and is also voiced by Carell).

Anyway, the villain: He’s a former TV child star called Balthazar Bratt, whose fame fizzled out in the 1980s. His bitterness — and perhaps his decision to maintain a tragically misguided mullet — has led him to attempt the theft of a gigantic diamond.

“South Park” guy Trey Parker does Bratt’s voice, which goes a long way to making the character click. But you also get the feeling that the filmmakers had more fun doing this character than anything else in the movie.

When Bratt builds a giant robot of himself and descends on Hollywood seeking revenge (he plans to lift L.A. into the sky with giant wads of bubble gum), you get a glimpse of what the movie could have been.

As for the Minions, whose strange language has made them popular in every corner of the world, they squeak and hop as per usual. A subplot puts them on a TV talent show where they translate Gilbert and Sullivan into their own lingo (very funny) and then prison (not so funny), which basically sidelines the little guys for too long.

This is one trip to the well too many for this franchise. But I wouldn’t mind seeing the Balthazar Bratt spin-off film, if they let Trey Parker write it.

“Despicable Me 3” (1 1/2 stars)

This uninspired sequel feels like three ideas cobbled together in disconnected skits — even the Minions are sidelined. The best stroke has a former 1980s TV child star (voiced by Trey Parker) as the villain, but even he can’t carry the movie.

Rating: PG, for violence

Opening Friday: Alderwood, Alderwood Mall, Edmonds Theater, Everett Stadium, Galaxy Monroe, Marysville, Stanwood Cinemas, Meridian, Oak Tree, Pacific Place, Thorton Place Stadium, Woodinville, Blue Fox Drive-In, Cascade Mall, Oak Harbor Plaza