According to two sources familiar with the matter, Warner Bros. Discovery Inc. is on the verge of a deal to create a new online TV series based on the Harry Potter book series Bloomberg.

The sources, who spoke on condition of anonymity because the deal has not been officially announced, said each season of the show will be based on one of JK Rowling’s seven novels. The company hopes the series will be a cornerstone of a new streaming strategy that parent company Warner Bros. will announce for HBO next week. David Zaslav, CEO of Warner Bros., and Casey Bloys, chairman of HBO, have been working to convince Rowling to produce the new series, but a deal has not yet been finalized.

The new series would allow the writers to further explore Rowling’s vast universe, as many of her books are more than 500 pages long. Warner Bros. previously adapted each of the seven Harry Potter books, culminating in a two-part film based on the final novel. However, Warner Bros. always wanted to do more with one of the best-selling book series of all time. And while Rowling has approved the theatrical adaptation and the theme park attraction, she has yet to give her approval for any new movies or TV shows.

The author will be involved in the series to ensure it remains loyal to her original material but will not run the show day to day or serve as its primary creator.

Warner Bros. is preparing to announce a new streaming strategy, including the name Max for its flagship online service, which debuted as HBO Max. The company’s vast library of programs, including Rowling’s Wizarding World, the Lord of the Rings films, and a league of superheroes such as Batman, Superman, and Wonder Woman, will play a crucial role in this strategy.

Zaslav announced that he wants to invest in fewer films and series in order to produce higher-quality content. The company announced in February that it would be making a new series of films based on The Lord of the Rings, but details have yet to be confirmed.

The Harry Potter brand has spawned several successful spin-offs and products. In February, Warner Bros. published Hogwarts Legacy, an RPG based on the world of Potter in partnership with Avalanche Software.

According to US publisher Scholastic Corp., over 25 years, the Harry Potter book series has sold 600 million copies in 85 languages, making it the best-selling book of all time. The eight films based on the series have grossed more than $7.7 billion worldwide, according to Box Office Mojo.