Michael King’s review published on Letterboxd :
Look, I realize how foolish it must seem to look for a well written story inside of the second money-grubbing sequel in an animated children's franchise that wasn't created by Disney or Pixar. Especially one that features The Minions(gag). But "Despicable Me 3" really had potential to be a solid film, and I think that's why I was so let down by it. If you look at the setup of this plot, it's just sitting on a tee, waiting to be sent over the fence.
I'm not going to harp on every single thing that this film bungled because I have better things to do with my life, but I will walk you through the second biggest complaint I have. My biggest complaint is the Minions being in this film to begin with, but I know that's a lost cause.
To start the film, you have this incredible contrast between Gru and his long lost twin brother Dru. Not only are they literally dressed in opposing black and white outfits, but Dru is everything that the recently unemployed Gru feels he is not: happy, rich, outgoing, and loved, with a full head of hair to boot. Gru's own wife and children even take a liking to Dru, adding to Gru's jealousy. So you can probably finish the plot from there, right? They'll butt heads over their different personalities, resulting in a big fight that drives them completely apart. Maybe Dru is even a good guy who wants to go bad, to contrast with Gru as the bad guy gone good, and discovering that is the last straw for Gru, because he's found a reason to justify his mistrust of Dru. But in the end, they'll put their differences aside for the greater good, to save the ones they love from danger. When they reconcile, Dru might reveal that despite all of his money and good looks and charming personality, it was he who was actually jealous of Gru, for the one thing Gru has that he doesn't: a loving family! Bada bing, bada boom, happy ending. Add some Minions farting or whatever it is they do during the credits and you've got a picture... Right?
Well, the writers for this film took a different route, and not one that will revolutionize the contemporary story arc, either. While they do hit some of the plot points I suggested above, they do so weakly, out of order, or from the totally wrong angle. The twin brothers butt heads for all of about two scenes, before immediately bonding over villainy when Dru reveals that their father was a famous super-villain, who was actually proud of Gru and disappointed in Dru. It's a weird backstep for Gru as a character at this point in the trilogy, and it really muddles things to have the brothers in harmony before the climax. Where is the conflict to be resolved in the third act? Well, the conflict arises when Gru lies to Dru about his intention to return the stolen diamond that they stole back together to the Anti-Villain League in order to get his old job back. It's just strange to have this conflict arise over the protagonist doing the right thing, because then Gru has to apologize for doing the right thing when he needs Dru's help saving his family. It doesn't help that their reconciliation is so underwritten, either. Basically, "I need your help." "Okay, I'll help." The third act desperately needed some emotion here, and we got nothing. So Dru helps, they save the city, and Dru comes to lives with Gru's family, without ever really resolving their conflict, which was thin to begin with. And, to top it all off, Dru's weak redemption arc is undone anyway in the epilogue, when he steals a rocket ship with the minions and blasts off, presumably to go commit villainous acts. So, that was a waste of our time.
And I know I said I wasn't going to focus on them, but I just have to mention that the Minions, despite unnecessarily taking up at least a third of the screen time and literally being in the same geographic location when the climax takes place, do not provide Gru with one ounce of assistance, apart from popping the huge gum bubbles after the hard work is over. They even have an easy counterpart in Balthazar's army of toys that they could have fought. Or the separate objective of saving Gru's kids while he fights Balthazar. It's just infuriating how many opportunities this script misses.
There's many other things that this movie gets wrong, too. Too many characters, too many story-lines, some mildly racist character designs. I could go on, but it's much more efficient to list the few things this film got right: the character of Balthazar Bratt, brought to life by Trey Parker's great voice acting, and the animation itself, which is splendid and colorful. That's it. Lesson learned: don't expect anything more than toilet humor and lazy writing from the Minions franchise.
For more of my thoughts on this film, check out this episode of the weekly drunken movie review podcast How Many Fingers Am I Holding Up?