King was born in New York. She appeared in her first commercial when she was six months old. When she was about five years old, she appeared in Inherit the Wind as Melinda. She studied voice and dance at the London Royal Academy. King is a member of the Joseph Jefferson Theatre Company, and her professional credits include summer stock and Off-Broadway productions. She appeared in Between the Lines (1977), Saturday Night Fever (1977), and Hair (1979) in uncredited roles.
After the success of Friday the 13th, she was pursued by a stalker. The stalker drew on some of her paintings, and tried to break the door down in her apartment. Shaken by the experience, she decided to take a break from acting and focus on painting.
In 2008, she was approached to appear in the reboot of Friday the 13th. Days later, the production contacted her again, stating that they had reconsidered and now wanted no one from the original to appear in the reboot. Shortly thereafter, she signed on to the science fiction/horror film Walking Distance, marking her first onscreen film appearance in 27 years. In 2012, she starred in the Welsh Christmas horror film Silent Night, Bloody Night: The Homecoming, an unofficial sequel to the 1974 American horror film Silent Night, Bloody Night.