The television series Star Trek: The Next Generation featured several characters in important roles. Counselor Deanna Troi, played by Marina Sirtis, was a half-human, half-Betazoid who served as the ship's counselor and diplomat. Worf, played by Michael Dorn, was a Klingon who served as the ship's security officer. Geordi La Forge, played by LeVar Burton, was a human engineer who served as the chief engineer of the USS Enterprise-D.