She began her professional career in Hong Kong, with starring roles in the action films Gen-Y Cops (2000) and Naked Weapon (2002), before appearing in the American productions Mission: Impossible III (2006), Live Free or Die Hard (2007), Priest (2011) and The Protégé (2021).

She portrayed Tori Wu in the dystopian science-fiction action film Divergent (2014), and reprised her role in the sequels, Insurgent (2015) and Allegiant (2016).

[7] She won an athletics scholarship to a private university and intended to study veterinary science; however, her family was unable to assist her financially.

[14] At a friend's suggestion, Q began modeling in Tokyo, Japan at the age of 17, before making an unsuccessful move to Taipei, Taiwan.

Her appearance in Gen-Y Cops impressed Chan so much that he cast her in his films Manhattan Midnight and Rush Hour 2.

She also stars in the video game Need for Speed: Undercover as the seductive lead character, federal agent Chase Linh, the player's only contact to the Tri-City Police.

[22] In 2010, Q became the lead character, an assassin gone rogue, on the CW series Nikita, based on the 1990 French film of the same name.

[27][28] In 2014, Q played the role of Dauntless faction member Tori Wu, in the film Divergent, the adaptation of the eponymous novel.

She also starred in the CBS drama series Stalker[29] by Kevin Williamson as Detective Beth Davis along with Mariana Klaveno and Dylan McDermott.

[34] In October 2013, Q started filming for The Crash, starring alongside Frank Grillo, AnnaSophia Robb, Dianna Agron, John Leguizamo, Ed Westwick, Mary McCormack, Christopher McDonald and Minnie Driver.

[35] The film was directed by Aram Rappaport and produced by Hilary Shor, Atit Shah and Aaron Becker.

[37] In February 2016, it was announced that she would co-star opposite Kiefer Sutherland in the ABC drama series Designated Survivor as Hannah Wells, a leading FBI agent.

[39] She starred as an assassin in The Protégé, an action film featuring Samuel L. Jackson and Michael Keaton, which was released to theaters August 20, 2021.

[40] In March 21, 2024, it was announced that she was cast as Homicide Detective Renée Ballard in the Bosch spin-off series centered around Michael Connelly's character.