Trained at San Francisco's American Conservatory Theater (ACT), McCormick played in her first feature, the interesting science-fiction saga, "Enemy Mine" (1985), while completing her graduate studies. She joined the company of the ACT for a time thereafter, but TV work picked up when she joined the cast of the ABC detective series, "Spenser: For Hire", during its second season in 1986 to play Rita Fiori, feisty young assistant D.A. and romantic sparring partner for series star Robert Urich. McCormick subsequently did regional stage work and played a recurring role as Minuet, a computer-generated ideal woman, on the popular science-fiction series, "Star Trek: The Next Generation". Occasional feature work, as in "A Simple Twist of Fate" (1994), came her way, but McCormick was primarily seen as intelligent police psychiatrist Elizabeth Olivet, another recurring role, on most of the series episodes of NBC's acclaimed "Law & Order" from 1991 to 1997. In the fall of 1997, she moved to ABC as the unhappy wife of a police psychiatrist played by Robert Pastorelli in the short-lived Americanized version of "Cracker".