Ellen McLain is an American opera singer and voice actress from Nashville, Tennessee. She is known for providing the voice of GLaDOS, the computer antagonist of the Portal video game series, the voice of the Overwatch in Half-Life 2 and Half-Life 2: Episodes 1 & 2, the voice of the Jaeger A.I. in Pacific Rim, and the Administrator, the narrator of the video game Team Fortress 2.