Broadway's The Sound of Music will have its third Captain Von Trapp on Mar. 10, when Richard Chamberlain joins the cast. Michael Siberry was the first, opening the revival March 12, 1998; he was replaced by Dennis Parlato, Nov. 4, 1998. Chamberlain takes over for a 17-week NY stint followed by a national tour, where he will be joined by Meg Tolin as Maria.

As for the New York cast, Laura Benanti is the new Maria Rainer, replacing Rebecca Luker, who originated the revival role. Another addition to the cast is Lenny Wolpe as Max Detweiler. Furthermore, Jeanne Lehman assumed the part of the Mother Abbess Feb. 2.

Richard Chamberlain's last Broadway role was in another golden-age musical, My Fair Lady, opposite Melissa Errico. The "Shogun" star is also well-known in theatre circles for a show that never made it to a Broadway opening night: Bob Merrill's Breakfast At Tiffany's, with Mary Tyler Moore, Sally Kellerman and Larry Kert.

Benanti, age 19, has been playing a nun in Music and has been the understudy Maria for several months. According to a production spokesperson at the Peter Cromarty office, Benanti had been at New York University exactly a week when she landed the nun gig at Music and chose Broadway over academia. She had previously done roles at NJ's Paper Mill Playhouse.

The 1959 Rodgers and Hammerstein musical tells the story of a singing would-be nun who transforms the lives of an Austrian widower submarine captain and his seven children through the power of goodness and song. She abandons the convent life to become the captain's wife -- just as the Nazi anschluss makes him a prime target for drafting into the German navy. Songs include the title tune, "Edelweiss," "My Favorite Things," "The Lonely Goatherd" and "Something Good." For tickets and information on The Sound Of Music at the Martin Beck Theatre call (212) 239-6200.