Jackie Earle Haley, born July 14, 1961, is an American actor whose career includes significant voice-over work in animation. He began his professional life as a child actor, and his earliest roles in the medium were voice parts in animated television series. In the early 1970s, he lent his voice to characters on shows such as Wait Till Your Father Gets Home, These Are the Days, and Valley of the Dinosaur. His first known role in television, in fact, came from providing the voice of the classic comic strip character Dennis the Menace in a series of animated commercials when he was five years old, a role he later reprised for episodes of the series Curiosity Shop.

While Haley is widely recognized for live-action performances in films like Watchmen, Little Children, and the A Nightmare on Elm Street remake, his most prominent connection to the anime genre is the role of Grewishka in the 2019 film Alita: Battle Angel. Directed by Robert Rodriguez and produced by James Cameron, the film is a live-action adaptation of the cyberpunk manga series Gunnm, also known as Battle Angel Alita, by Yukito Kishiro. In this film, Haley portrayed the vicious cyborg mercenary Grewishka, a supporting antagonist who repeatedly confronts the title character. His performance in Alita: Battle Angel was realized through motion-capture and CGI, a process that records an actor's physical performance to drive a digital character, rather than traditional voice-over work.

Beyond this notable credit, Haley has additional voice acting roles. He is credited as a voice actor in the 2022 animated film My Father's Dragon, where he played the character Tamir. His filmography also lists a voice role in the 1990 animated series Rick Moranis in Gravedale High. According to available records, his complete body of work includes two credits specifically for voice performance, alongside his extensive work as an on-screen actor.

While his direct work in Japanese anime or its direct adaptations is limited primarily to his performance capture role in Alita: Battle Angel, Jackie Earle Haley has a long-standing history with animation that began in his childhood. His career demonstrates a versatility that spans live-action character acting, motion-capture performance for a Hollywood manga adaptation, and traditional Western animation voice-over.