The Pennsylvania native made his Broadway debut in a small role in the original Broadway production of "A Streetcar Named Desire" and went on to remain active on stage well into the 1970s. On the small screen, Karen debuted as Bob Cratchett in the 1948 live NBC production of "A Christmas Carol". Daytime fans may remember him for his stint as Linc Tyler in ABC's "All My Children" during the show's first year in 1970 while primetime fans may recall him as either Dick Van Patten's editor/boss on "Eight Is Enough" or as Major Wymore, Lou Gossett's boss, in "The Powers of Matthew Star" (NBC, 1983).
A prolific actor, he has appeared in a number of TV-movies and miniseries as well as feature films, beginning with several low-budget horror pictures in the mid-1960s, including "Frankenstein Meets the Space Monster" and the quickie action adventure, "Hercules in New York" (both 1965). Classy pictures came in the 70s, including a turn as Hugh Sloan's lawyer in "All the President's Men" (1976). In 1982, Karen was Teague, the real estate agent who gets his comeuppance in the last scenes of "Poltergeist". Still active in the 90s, he was Bill Rogers, former law partner and secretary of state, in "Nixon" (1995), Tom Orr, watching Robert Redford and Michelle Pfeiffer in "Up Close & Personal" (1996) and appeared in the supporting ensemble of "Apt Pupil" (1998).