The critic Stark Young, asked to a concert during the early years of Martha Graham’s career as a dancer-choreographer, is said to have replied, “Oh, must I go? I’m so afraid she’s going to give birth to a cube on the stage.” He then sent Graham a reliquary of a saint’s robe. The 1930 work Lamentation embodies both images in one dance. Encased head to ankles in a tube of purple stretch tricot—a costume designed by Graham herself—we see suffering as if it were a birth throe, a robed release. That fabric is a reliquary that contains the body, which with knees, arms, and elbows, angled and straightened, pulls into Cubist forms that shift with every wave and tug of feeling. If the world didn’t yet know that young Graham was a genius, Lamentation opened its eyes. Newly discovered film footage of this seminal work will be presented on April 22 and 25 at two-thirty P.M., along with other coverage of the work. The show will then be accessible on the company’s YouTube channel. —L.J.