Theremin was interested in a role for the theremin in dance music. He developed performance locations that could automatically react to dancers' movements with varied patterns of sound and light. He worked with the American Negro Ballet. After the Soviet consulate had apparently demanded he divorce Katia, the inventor fell in love with and married the young prima ballerina Lavinia Williams. His marriage to the African-American dancer caused shock and disapproval in his social circles, but the couple remained together.