Whale Rider director Niki Caro has signed on to write and direct Callas, about the legendary opera star Maria Callas, based on the book "Too Proud, Too Fragile" by Alfonso Signorini, who will also take a writing credit on the film.

"We fully expect Callas to become one of the most important films in the De Angelis dossier as the source material provided by Mr. Signorini's book is the most in-depth to date about the life of the controversial opera star. We've put together a very strong production team from Niki Caro on to bring this story to screen," said the De Angelis Group's Andrea Zoso.

No production date has been set.