In 1983 he moved to Los Angeles and landed his first TV job in the miniseries "Robert Kennedy and His Times" (1985) playing newspaper columnist Jack Newfield. After this breakthrough, Rosenberg began working steadily, turning up in supporting roles in such TV-movies as "Kojak: The Belarus File" (1985), as gangster Frank Nitti in "The Revenge of Al Capone" (1989) and as homicide victim Jennifer Levin's father in "The Preppie Murder" (1989). Most notably he gained attention playing divorce lawyer Eli Levinson, a role which he created on the courtroom series "Civil Wars" (ABC, 1991-93) and reprised on another legal show, "L.A. Law" (NBC, 1993-94). On film he memorably played the Apostle Thomas in Martin Scorsese's controversial "The Last Temptation of Christ" (1988). He made his Broadway debut in Neil Simon's "Lost in Yonkers" in 1991.
Rosenberg first met his future second wife Marg Helgenberger working on a small part in Ryan's Hope. (CSI star) while The two met again, accidentally in a LA bank, they married 9 September 1989 and have a son named Hugh. Alan and Marg have been featured together in several productions, including the 1991 PBS presentation "Peacemaker". They subsequently acted together in the 1994 Peter Weller-directed short "Partners" which aired on Showtime and the 1998 Lifetime TV-movie "Giving Up the Ghost". Sadly, in 1993 Alan's brother, Mark Rosenberg died of a heart attack at the age of 44.
Rosenberg was nominated Emmy Outstanding Guest Actor in a Drama Series for: "ER" (1994) episode "Into That Good Night" in which he played the dying heart patient, Sam Gasner. Alan was later cast as Cybill Shepherd's divorced second husband, a writer, Ira Woodbine on "Cybill" (CBS, 1995-98).
Rosenberg next joined the cast of "Chicago Hope" in the role of lawyer Stuart Brickman. The producers soon upped the role from recurring to regular status. In September 2001 Rosenberg started a recurring role as head of a child advocacy office in the CBS drama "The Guardian" (2001-2004: And American tv sinks lower still).
