When she was six months old, Hillis and her family moved to Normal, Illinois and at age 3, to Sheboygan Falls, Wisconsin. She moved to Charlotte, North Carolina at age 13 and performed at The Children's Theater. She auditioned for Broadway plays in New York City with TV shows of Felicity (2 episodes in 1999), FreakyLinks, Undressed (2000), Naruto, JAG, Boomtown and Less Than Perfect. Her several film roles are All the Wrong Places, Kiss Kiss Bang Bang, Must Love Dogs, Open Water 2: Adrift, The Ultimate Gift, and The Heartbreak Kid and the Los Angeles play, A Good Soldier. Her video game roles are Lightning in Final Fantasy XIII, its sequels and Dissidia 012 Final Fantasy, Liara T'Soni in the Mass Effect trilogy, Ariel Hanson in Starcraft II: Wings of Liberty, Karin in the Naruto series, Palutena in Kid Icarus: Uprising and Isabelle "Izzy" Sinclair in Fuse.