As Gru struggles to figure out his next move, a mysterious stranger appears informing Gru that he has a long-lost twin brother named Dru, who would very much like to meet him. Initially excited about the prospect of having a brother, Gru takes Lucy and the girls to his homeland of Freedonia to meet his twin… only to find that Dru is seemingly better than him in every way. While Gru is bald, misanthropic and newly unemployed, Dru has a gorgeous, full head of hair, is effortlessly charming, and has inherited their father’s pig farm along with a large fortune. Gru is quickly overwhelmed by a feeling of inferiority, but it isn’t long before Dru reveals he has a secret desire of his own: to follow in their father’s footsteps of becoming a world-class villain.
When Gru realizes he can partner with his brother and use their dad’s highly sophisticated, villainous gadgets to finally take down the elusive Balthazar Bratt, he agrees to form an alliance with his twin. But when that alliance is seriously tested by a delayed case of sibling rivalry, the brothers quickly find themselves in way over their heads, as Bratt proves to be Gru’s most challenging nemesis yet.