Dancer Marc Platt was the male lead in the famed dream ballet in "Oklahoma!" on Broadway, choreographed by Agnes de Mille. In film, he was one of the brothers in "Seven Brides for Seven Brothers," and he had featured parts in several other musicals.

But his favorite role came before he danced on Broadway or in the movies. In his early 20s, Platt was one of the first Americans to join the Ballet Russe de Monte Carlo, one of the seminal ballet companies of the 20th century. Whisked from Seattle into the exotic, world-traveling troupe, he was forced to Russianize his name and given some key roles, including the Spirit of Creation in legendary choreographer Léonide Massine's "Seventh Symphony" that Platt danced in a short white tunic.

"This is the best dancing role I ever had," said Platt in the 2005 documentary film "Ballets Russes," holding up a black-and-white 1938 photo of himself in the outfit. "Just danced my fool head off."

Platt, who celebrated his 100th birthday in December, died Saturday in a hospice facility in San Rafael, Calif. The cause was complications from pneumonia, said his daughter, Donna Platt.

He was born Marcel Emile Gaston LePlat in Pasadena on Dec. 2, 1913, the only child of a concert violinist and soprano singer. The family traveled a lot for performances and finally settled in Seattle. When his father died around the time of the move, his mother "got a job in Mary Ann Wells' dancing school," Platt said in a 1946 Hedda Hopper column that ran in the Los Angeles Times. "I wanted to help buy the bacon, so I got a job as an errand boy at the same school."

But Wells saw his potential as a dancer, and after eight years of lessons, she arranged for him to audition for Ballet Russe when the company visited Seattle.

He was shown in to meet Massine, the artistic head of the company. "I shook hands with him, and he said 'Go dance,'" Platt said in the documentary. "I said 'Yes sir, I have a war dance but I don't have any music and can I do it in bare feet?'"

Massine said nothing after Platt danced, but five days later he was invited to join the company. Under protest, he was given the name Marc Platoff to maintain the illusion that everyone in Ballet Russe was from Russia. Despite the opulence of the company's productions, Platoff's pay was $150 a month.

He left the company in 1942 to try to break into Broadway and make more money. After he changed his name to Marc Platt, he was cast in some short-lived shows before landing "Oklahoma!," which opened in 1943. In the lengthy dream sequence, Platt played the lead part of Curly. New York Times critic Lewis Nichols described him as an "important" dancer.

After about a year in the show's run, Columbia Pictures signed him to a contract and he got a part in the 1945 Rita Hayworth film, "Tonight and Every Night," in which he had a solo reminiscent of his Ballet Russe audition. He plays a dancer who doesn't bring music to a tryout but instead performs to whatever is on various radio stations, whether it is opera or swing. His best-known film role was in the dance-laden musical "Seven Brides for Seven Brothers" (1954), in which he played Daniel.

In the 1960s, Platt directed the ballet company at Radio City Music Hall in New York City and had a dance school with his wife, Jean Goodall. They eventually moved to the Fort Myers area in Florida and ran a school there until shortly after Goodall's death in 1994. A previous marriage to Ballet Russe dancer Eleanor Marra ended in divorce.

Platt settled in Northern California near family members. He occasionally appeared in shows produced by the Marin Dance Theatre in San Rafael. "See, that's what happens to dancers," he said in the documentary while putting on makeup at age 89 for his non-dancing part in a performance of "Sophie and the Enchanted Toyshop."

"Then they get older and they really don't want to leave it," he said.

In addition to his daughter Donna, who lives in San Rafael, Platt is survived by sons Michael Platt of West Des Moines, Iowa, and Ted LePlat of Santa Monica; and a granddaughter.

david.colker@latimes.com