Ellen McLain

Ellen McLain (born December 1, 1952) is an American opera singer and voice actress from Nashville, Tennessee. She is best known for providing the voice of GLaDOS, the computer antagonist of the Portal video game series and "The Witch", a crying female zombie who can easily incapacitate or kill any player who startled her, from Left 4 Dead and Left 4 Dead 2. Her voice roles also include the Jaeger A.I. in Pacific Rim, the Combine Overwatch in Half-Life 2 and the Administrator, the announcer of the video game Team Fortress 2.