"Obviously there's a special significance for portraying Catwoman," Rivera told ET before we see her doing voiceovers as the famous comic book character.
"Every actress that I've ever loved has played Catwoman in some shape or form," she continued. "I'm honored I get to play it for this movie."
The late actress voices Selina Kyle, aka Catwoman, in the two-part animated film. Inspired by the '90s comic run of the same name, The Long Halloween sees the Caped Crusader setting out to solve a string of holiday-centric murders in Gotham City. Along the way, Batman's path will cross with some of his most infamous rogues.
While her role as Catwoman may be Rivera's final act on screen, the late actress' father, George, told ET that her final act of strength in life was saving her son, Josey, 5, after their boat started drifting while on a trip to California's Lake Piru in July 2020.
When asked what that final heroic act says about Naya, George shared, "Sort of the same mantra she used for life, you know, preservation, keep going, when things are hard, you keep pushing. It just shows you the strength of the person."
George told ET that Josey was definitely Naya's number one priority and that last act of strength was proof of that.
"He really became everything for her," he said. "Her focus was really on him and he was growing up as she was becoming a mother, she really leaned into that, really leaned into that and the word I want to use is maturity. She became very mature as a person and really receptive to other people's feelings."
He added that motherhood changed the late actress in the best way. "I watched the maturity in her after she had a child, before and after, big difference," he shared.
Just last week, Josey graduated from Pre-K. His dad, Ryan Dorsey, took to Instagram Saturday to share a photo alongside the 5-year-old, who proudly wore a black cap and gown, as he sat on his dad's knee.
"Fresh outta Pre-K boy! Next Up Kindergarten! #summertime #proudDad," Ryan captioned the photo.