Dirty Politics author Nicky Hager will release his next book on Tuesday, Newshub has confirmed.
The title and topic are still a mystery, but Unity Books in Wellington has confirmed to Newshub it will be revealed on Tuesday at 5:15pm.
"The book is not a sequel to Dirty Politics nor related to the election," Hager said in an email.
"It is a completely different book but nonetheless gripping and important."
Unity staff told Newshub they didn't know what it would be about, and won't until the boxes arrive and are opened on Tuesday.
Hager is declining to talk about the book until it is released.
Dirty Politics, released in the lead-up to the 2014 election, was highly controversial.