In this image, the dancers are incredibly angular in their movements. Their arms, legs, and bodies all form angles and lines, all very sharp and pronounced. The lighting very clearly matches this--the spotlights are shaped to squares, each one individually lighting the dancer. The shadows are also very angular, and there are not other sources of light on the stage.
This dance lighting puts all emphasis on the dancer's body. Instead of lighting any part of the dancer, everyone on stage is cast in shadow, creating full silhouettes. The only light on stage is some colored cyc lights, resembling a sunset. This brings attention to every movement of the body, making the dancer stand out.