Quartet is a rigorously formal chamber ballet. The minimalist score and unisex costumes create a neutral atmosphere in which the four dancers move with atomic precision. The choreography is grounded in a classical vocabulary “with Twyla's unusual way of switching weight,” describes principal ballerina Cynthia Gregory. The geometric formality is punctuated with unexpected entrances, exits and changes in direction. “When you want to go one way, she has you go the other. The whole torque of it is unique."