The Belgian choreographer Anne Teresa de Keersmaeker founded the dance company, Rosas, in 1983. Her astonishing dances were muscially and structurally rigorous—almost mathematical—yet they spoke lyrically of the heart and human nature. Here’s a chance to see a very early work, the second she created, 1982’s Fase, Four Movements to the Music of Steve Reich. De Keersmaeker is a member of the team bringing a new West Side Story to Broadway this December. So do your homework. —L.J.