Sasha Waltz’s choreography is raw and conceptual, her dancers often unclothed, their bodies braving extreme situations that pose existential questions. So it should be interesting to see Waltz’s staging of a Baroque opera, shapely and contained, and not just any Baroque opera, but Purcell’s rose-cut diamond of 1689, the tragic tale of Dido and Aeneas. Waltz will soon begin co-directing, along with Johannes Ohman, the Staatsballett Berlin. —L.J.