Mr. Chamberlain made his film debut in “The Secret of the Purple Reef” (1960), a crime drama set in the Caribbean. He agreed to exploit his Kildare image by playing a young doctor in “Joy in the Morning” (1965), a lightweight drama about newlyweds, with Yvette Mimieux. That did not call for (or yield) a particularly complex characterization. But he went on to give several memorable — and, at that time, surprising — film performances.
They included Julie Christie’s dangerous husband in “Petulia” (1968), Octavius in “Julius Caesar” (1970), Tchaikovsky in “The Music Lovers” (1971), Aramis in “The Three Musketeers” (1973) and its sequel, the cowardly electrical engineer in the disaster film “The Towering Inferno” (1974) and an Australian lawyer transformed by an encounter with Aboriginal culture in Peter Weir’s drama “The Last Wave” (1977).
His stage career got off to an unfortunate start with the disastrous 1966 Broadway musical adaptation of “Breakfast at Tiffany’s,” also starring Mary Tyler Moore, which closed in previews. But he later earned admiring reviews for classic roles in “Richard II” and “Cyrano de Bergerac,” as well as in “Hamlet.” In the 1970s he was nominated twice for Drama Desk Awards, for his portrayal of a fallen minister in Tennessee Williams’s “The Night of the Iguana” (1976) at the Circle in the Square and of Wild Bill Hickok in “Fathers and Sons” (1978) at the Public Theater. He called Hickok his favorite role.
He returned to Broadway, if not triumphantly at least to more than respectful reviews, in “Blithe Spirit” (1987) and “My Fair Lady” (1993), and as a replacement in “The Sound of Music” (1999). (The musicals reminded longtime fans that he had a hit record in the ’60s, singing the “Dr. Kildare” theme.)
In addition to the mini-series, he appeared in numerous made-for-television movies, playing the title roles in “F. Scott Fitzgerald and ‘The Last of the Belles’” (1974) and “The Man in the Iron Mask” (1977). He starred in another series, “Island Son,” in 1989, playing yet another doctor, but he was unhappy with its direction and it lasted only one season.
After his formal coming out, Mr. Chamberlain appeared to delight in portraying characters who were gay or played with gender stereotypes. He had already appeared on the sitcom “The Drew Carey Show” in full drag as a female character. He was later a guest star on “Will & Grace” and made a cameo appearance in the film “I Now Pronounce You Chuck & Larry” (2007).