The author of the mega-selling “Harry Potter” series has a new book deal, and it has one big difference from the “Potter” books, The Huffington Post reports.

JK Rowling’s next book will be aimed at adults.

The story reports: “The writer behind the wildly popular ‘Harry Potter’ series has finalized a deal with Little, Brown for her forthcoming novel, which will be available both in print and e-books. This will mark a departure from her previous publishers, Bloomsbury in the UK and Scholastic in the U.S.”

Details about the new project have not been released.

Rowling said in a press release: "The freedom to explore new territory is a gift that Harry’s success has brought me, and with that new territory it seemed a logical progression to have a new publisher.”