Diana is an immortal, 5,000-year-old Amazon princess, demigoddess daughter of Hippolyta and Zeus, and the half-sister of Ares, who, in the present day, lives in France working under the name of "Diana Prince" as an antiquities dealer while moonlighting as the superheroine referred to as "Wonder Woman."

She is also an ally to the masked vigilante Batman. Gadot described her character as having "many strengths and powers, but at the end of the day she's a woman with a lot of emotional intelligence". As to how her character is different from her appearance in Batman v Superman: Dawn of Justice, Gadot said "We go back 100 years to when she's more naive", further explaining, "She's this young idealist. She's pure. Very different to the experienced, super-confident, grown-up woman you've seen".

Gadot underwent a diet and training regimen, practiced different martial arts and gained 17 pounds of muscle for the role. Élodie Yung and Olga Kurylenko had also auditioned for the role. Gadot was previously offered a role in Man of Steel, which she declined because she was pregnant at the time; this allowed her to later be cast as Wonder Woman in the film's follow-up. Gadot signed a three-picture deal and debuted in Batman v Superman: Dawn of Justice.