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Cassandra Cain (DC Extended Universe)
Birds of Prey Character Posters 05

Name: Cassandra Cain
Aliases: N/A
Species: Human
Nationality: Asian/American
Marital Status: Single
Occupation: Juvenile Pickpocket

- Harley Quinn Associates

Last Known Residence:
- Gotham City, East End District


Cassandra Cain grew up in a Janus Foundation public housing building in the East End district of Gotham City. Possessing neglectful foster-parents, Cassandra spent most of her time wandering the streets and developed a street-tough attitude and a talented habit of pickpocketing. She first saw Harley Quinn while sneaking into and watching a roller derby match in the East End.

When Roman Sionis sends Dinah Lance and Victor Zsasz, to retrieve the Bertinelli Diamond; a diamond embedded with the account numbers to the fortune of the Bertinelli crime family, Cassandra pickpockets the diamond from Zsasz's pocket during a thieving spree but is caught and arrested by the Gotham City police. Trying to stash her plunder while in the back of the police car, Cassandra swallows the diamond. Returning to the Janus Club, Zsasz informs Roman that Cassandra had the diamond and Dinah warns Detective Renee Montoya that Roman had placed a bounty on Cassandra's head to retrieve the diamond. As Roman prepares to have Harley Quinn executed for her past indiscretions against him while under the Joker's protection, she offers to find Cassandra and recover the diamond for him. Breaking into the GCPD, Harley frees Cassandra while also fighting off bounty hunters seeking Cassandra's bounty. She and Cass bond while hiding out at Harley's apartment.

When Harley's apartment is bombed by criminals looking for Cass, Harley becomes depressed over being constantly betrayed by those she trusted and calls Roman with an offer to turn Cassandra over in exchange for his protection, agreeing to meet at an abandoned amusement park attraction called "The Booby Trap". Dinah notifies Detective Montoya of this meeting, but Zsasz notices her text message en route to the park and informs Roman. Devastated by Dinah's betrayal, Roman dons his iconic black mask to personally marshal his forces and kill Harley, Dinah and retrive the diamond. At the park, while Cassandra is tied to a toilet by Harley, Montoya confronts Harley but is knocked out of a window. Zsasz arrives and tranquilizes Harley before holding Dinah at gunpoint. He is killed by Helena Bertinelli; aka the Crossbow Killer/Huntress, who reveals Zsasz was the last of her family's killers she sought to kill in vengeance.
Montoya returns and a stand-off ensues when Cassandra frees herself and grabs Zsasz's gun. When Roman arrives with a small army of masked criminals to kill everyone within the park, using Harley's old gear, the women fight off Roman's goons, protecting Cassandra in the process, however, Cassandra is captured by Roman, and Montoya is shot but saved by Harley's bulletproof bustier. Dinah reveals her metahuman ability to scream at a supersonic level, allowing Harley to give chase on roller skates. Assisted by Helena and her motorcycle, Harley pursues Roman and Cassandra to a nearby pier, where Cass plants a grenade in Roman's pocket while he and Harley are talking, killing him as Harley throws the crime lord off the pier seconds before the grenade explodes.

In the aftermath of destroying Roman's criminal empire and retrieving the Bertinelli diamond, Montoya quits the GCPD and joins Dinah and Helena in becoming a group of vigilantes known as the "Birds of Prey" (founded by Helena's family inheritance), while, with the money gained from selling the diamond, Harley starts her own business with Cassandra as her protege.


  • Cassandra Cain is played by Ella Jay Basco.
  • Cassandra Cain first appeared in Birds of Prey (and the Fantabulous Emancipation of One Harley Quinn) (February 7th, 2020).
  • Cassandra is stated to be twelve years old during the events of Birds of Prey (and the Fantabulous Emancipation of One Harley Quinn).
  • To further prepare her for her role, Ella’s father (Derek Basco) gifted her a stack of DC comic books featuring Cassandra Cain. While what was portrayed in those comics was a bit different from what was brought to the big screen, the source material was said to have proven to be illuminating for the young actress.
  • Cassandra appears in the music video for Saweetie and GALXARA “Sway With Me” from the Birds of Prey soundtrack, where she sits in the back of a vintage yellow convertible screaming her head off and dancing as the singers sing their song. [1]
  • Gail Simone has been very effusive in her praise for the movie on her social media after seeing it at the press preview, though she, like many, didn't really care for the film's treatment of Cassandra Cain. She found the character within the context of the film enjoyable, but argued that she shouldn't have shared a name with an otherwise fundamentally different character. [2]
  • Fans of the comic book version of Cassandra Cain have started referring to the Cassandra Cain in this film as “Kassandra Kane" as a way to illustrate how different the character actually was from the source material.

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