Scientist assigned to Homeworld Command. Drs. McCormack and Williams used the communication stones to travel to the Destiny in the bodies of Chloe Armstrong and Eli Wallace, respectively, to assist Colonel Telford in an attempt to dial the ship's Stargate back to Earth while it recharged inside a star.
While on Earth, Chloe used McCormack's body to pose as "Cousin Liz." During a Janelle Monae concert, Chloe discovered McCormack's body was far less tolerant to alcohol than her own.
When the rescue attempt aboard Destiny failed, McCormack, Williams and Telford were ordered to evacuate to Earth, back into their own bodies.
Earth - McCormack is sent to the Destiny to try and dial Earth while inside a star.