Hilary Mantel has promised to use her third instalment of her Thomas Cromwell trilogy to "bring it home in style".
She said The Mirror And The Light, which is to follow her two Booker Prize-winning novels Wolf Hall and Bring Up The Bodies, would be a "complex" work charting Cromwell's fall from grace.
Mantel said she still had research to do on the final part of her celebrated historical fiction depicting the pivotal role of Cromwell in the court of Henry VIII.
"It's going to be a complex book, I guess in texture more like Wolf Hall than Bring Up The Bodies," she told BBC Radio 4's Today programme.
"I have four years to cover here, and what I want to do is hold up a mirror to everything that's gone before and shed new light on it.
"So what I'm trying to do is make three books that stand up independently, yet the third book will have to contain them all.
"And it still has to surprise the reader, and I guess it will surprise me in the writing. I still have work to do and research to do."
She added: "It will be complicated but I'm not intimidated. I think I can bring it home in style."