The Knife Doing Their Homework for Darwin Opera

Experimental Swedish pair the Knife have revealed the vigorous research behind their unique latest project, an opera about Charles Darwin's theory of evolution.

The brother and sister duo were commissioned by Danish performance group Hotel Pro Forma to compose the opera, entitled 'Tomorrow, In A Year,' which will be both performed live and released as an album.

"We started by reading a lot, for the first couple of months," said Olof Dreijer to BBC 6 Music. He and his sister Karin pored over both Darwin's original texts and modern analyses of Darwinism. "Lots of reading and experimentation. I would say the whole piece is a musical exercise on these books."

As well as grappling with the dense subject matter, the Knife had to learn the art of the opera -- a field neither of them have any experience in.

"It was really difficult at first," said Dreijer, "but after some months of learning how, for example, the opera singer thought and how she worked, getting her used to our way of thinking, it's interesting stuff but very difficult I think.

"I really have learned about how to become moved by the singer. That took a couple of months to come away from seeing her as a stereotypical opera voice because it's so different from my world."

Collaborating with the Knife on the opera are DJ Mt Sims and avant-garde singer Janine Rostron, otherwise known as Planningtorock.