Panettiere became most prominent as Claire Bennet in the NBC series Heroes, which was created by Tim Kring, as a high school cheerleader with regenerative healing powers.Thanks to her role on Heroes, she became a regular on the science fiction convention circuit, invited to attend conventions around the world in 2007, including Gen Con, New York Comic Con, and Fan Expo Canada.
She is known for her roles as cheerleader Claire Bennet on the NBC sci-fi series Heroes (2006–10), Juliette Barnes in the ABC/CMT musical-drama series Nashville (2012–present) and Kairi in the video game series Kingdom Hearts.
The appearance was engineered by her mother and involved a male "fan" discussing her work with her, instigating a jealous reaction from the man's spouse.
In April 2012, she hosted an episode of the new series.
In 2004, she played Kate Hudson's title character's adolescent niece in Raising Helen.
In 2005, she was the title character's rival in a skating contest in Ice Princess.