'Percy Jackson' author Rick Riordan ventures into Norse mythology.

After scoring with two previous children’s series about mythology, author Rick Riordan is now turning to Norse lore for his next few books.

“The Norse gods are so wild,” Riordan told the Associated Press. “They have this wild, barbaric energy you don't associate with the Greeks.”

Riordan wrote the wildly popular kids’ series “Percy Jackson and the Olympians,” based around a boy who discovers he’s the son of Poseidon and must join with as well as fight Greek deities such as Zeus, Hades and Medusa. The first book was turned into a movie last year, and the next movie is due in 2012.

Riordan followed up his “Percy” books with the Kane Chronicles, which center around a brother and sister who must fight off the evil Egyptian god Set. Two books have been released in the Kane series and the third is due next spring. The author is also juggling a new series called “Heroes of Olympus,” set in the same world as his “Percy” series but with a new cast of characters. The second “Heroes” book is due to be released tomorrow.

Riordan told the AP he had planned the Norse series even before his “Percy” books.

“There are so many fantastic stories and I want to bring Thor and Odin and the other gods into the modern world, just like I did with the Greeks and Percy Jackson,” he said. "I'll give the books an urban setting and have young people interacting with the Norse gods.”

Disney Publishing Worldwide has signed Riordan for at least three Norse books, but the author says the first probably won’t be released until 2015.

Molly Driscoll is a Monitor contributor.

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