At the beginning of the first film, Gru is an ambitious supervillain who constantly seeks approval from his mother, until the adoption of his daughters convinces him that their happiness is the most important thing.

In the second film, Gru leaves his villainous past behind to care for his adoptive daughters, but then soon joins forces —unwillingly— with secret agent Lucy Wilde, whom he later marries.

In the third film, after he and Lucy are fired from their jobs at the Anti-Villain League, Gru learns that he has a twin brother, Dru, whom he never met due to their divorced parents raising each child separately.

[5] Gru's distinctive accent, described as "quasi-Russian" by A. O. Scott[6] and "halfway between a Russian mafioso and a crazed Nazi" by Roger Ebert,[7] was largely a product of his voice actor Steve Carell's experimentation.

[8] According to Despicable Me producer Chris Meledandri, the voice Carell eventually settled on was conceived as "halfway between Ricardo Montalbán and Bela Lugosi".