Update (11:14 a.m.): Contrary to the earlier report, The Hollywood Reporter contends Carey will voice Gotham's mayor, not Commissioner Gordon. Original story continues below.
She joins a cast that includes Will Arnett as Batman, Michael Cera as Robin, Ralph Fiennes as Alfred, Rosario Dawson as Batgirl and Zach Galifianakis and The Joker.
Chris McKay ("Robot Chicken") is set to direct "The LEGO Batman Movie" from a script by Seth Grahame-Smith. Targeted for release on Feb. 10, 2017, it's the first follow-up feature to last year's "LEGO Movie," which grossed a whopping $468.8 million worldwide. It will be followed by a "Ninjago" spinoff and then a direct sequel to "The LEGO Movie."
Although far better known as a singer and songwriter, Carey has appeared in several films and television series, including "Glitter," "Precious" and "The Butler."