Julia Duffy filled in for 1 episode on October 18, 1977 and Kathryn returned for a few days until the character was permanently recast with theater actress Judith Light.

[3] As fiscally-responsible breadwinner Larry refused to dole out exorbitant allowances to pay for his fiancée's expensive tastes, Karen soon engaged in afternoon trysts with wealthy businessmen such as Talbot Huddleston (Byron Sanders) in order to afford luxuries.

In 1978, Karen (Light, onward) at last confided in her friend and media tycoon Victoria "Viki" Lord Riley (Erika Slezak) as to the details of the life she was leading.

Viki promised to keep Karen's lurid secret, and soon waged a public campaign of her resources as publisher of The Banner newspaper and other outlets against Marco's brothel, which masqueraded as a modeling agency.

Light's Karen lashed out on the stand at Llanview District Attorney Herb Callison (Anthony Call), revealing her secret life of prostitution to jurors and, for the first time, to her now-husband Larry.

Upon their meeting in 1983, the character of Karen said a final goodbye to rehabilitated former husband Larry and enemy-turned-friend Marco, leaving Llanview to enter witness protection and a romantic relationship with Steve in Canada.

Judith Light's portrayal of Karen in the Viki Lord Riley (Slezak)–Marco Dane (Anthony) murder caper brought the show critical acclaim and is credited with garnering One Life to Live ratings successes from the late 1970s into the early 1980s.