Paris prostitution goes on exhibit

The ballet rehearsal painted in 1874 by French artist Edgar Degas looks, at first glance, like an innocent portrayal of dancers limbering up for a performance. But who's that man in the shadowy background, straddling a chair, his top hat pulled down low over his eyes?

"Why is he there? What's he doing? Was he a member of staff of the Paris Opera? It's possible," said Professor Richard Thomson, one of the curators of a new exhibition at Amsterdam's Van Gogh Museum. "Or was he the lover of one of the dancers? Somebody who kept a dancer? These are the things we don't know."

Ambiguity is one of the key themes of the exhibition opening on Friday that explores artists' fascination with prostitution in Paris in the second half of the 19th and start of the 20th centuries.