The series features a main protagonist, Alex Udinov, who is canonically bisexual. Her past relationship with a woman is depicted in flashbacks as a meaningful part of her history, contributing to her character's complexity. The portrayal is respectful, avoids stereotypes, and integrates her identity naturally into the narrative, affirming her dignity and agency.

The show features multiple female characters, including Nikita Mears and Alex Udinov, who are highly skilled in martial arts and hand-to-hand combat. They consistently engage in and win physical fights against male opponents, often against multiple adversaries, throughout the series.

The lead character, Nikita, was consistently portrayed by white actresses in prior film and television adaptations. In the 2010 series, the role is played by Maggie Q, an actress of Asian and white heritage, which constitutes a race swap.