In 1984, King was nominated for a Golden Globe award for his role in the TV movie The Hasty Heart. That same year, he landed the role of Cody Allen on the series Riptide.
In 1993, he starred in the television adaptation of Sidney Sheldon's novel A Stranger in the Mirror, which is a roman à clef on Groucho Marx. In 1995, he portrayed the role of Hayley Armstrong on Melrose Place. He also appeared as Richard Williams in the NBC TV series Titans with Yasmine Bleeth in 2000 and as the President of the United States in the 2004 film The Day After Tomorrow.
King has made guest appearances on TV shows including Spin City, Will & Grace, Eve, and Cold Case.