It was time to tell the story again, and who better to tell it than Cicely Tyson? She was there, after all, in 1968, just after Martin Luther King Jr. was assassinated, when the African-American ballet star Arthur Mitchell called her to his apartment at 2 a.m. She was there when he asked, “What should we do?” and when he said, “I have an idea.”

The idea, and what became of it, was the reason that the 94-year-old Ms. Tyson, glamorous and charming, was at New York City Center on Wednesday. The occasion was the 50th-anniversary gala of Dance Theater of Harlem, the company that Mitchell formed (with the ballet teacher Karel Shook) to show that African-Americans could dance ballet — and excel at it. And Ms. Tyson was telling the origin story because Mitchell could not. He died in September.