‘Black Swan’ Is ‘Horrific,’ Says Royal Ballet Star: Interview

Sarah Lamb is held upside down by a dance partner, her legs like half-open scissors, as dissonant violin music screeches through a London practice studio.

Pale and pencil thin, the U.S.-born Royal Ballet principal is rehearsing a Wayne McGregor choreography created on her. As the ballet master asks her to tweak a movement, she says it’ll be hard -- “unless I can put my knee on my head.”