British author Justin Somper is a man of many hats: he worked as a children’s book publicist and owned his own publicity consultancy group, before creating the hybrid-genre series, Vampirates. According to Somper’s U.S. editor, Nancy Conescu at Little, Brown Books for Young Readers, the first four books in Somper’s series, popular in the U.K. (where they are published by Simon & Schuster U.K.), have now been translated into more than 20 languages—and are reaching a growing American readership.

The books, which take place in a flooded world beginning in the year 2505, follow the lives of two orphan twins, who are lost at sea. When Connor is rescued by pirates, and Grace by vampire-pirates, the two have very different experiences onboard their respective ships.

Besides the ready appeal of vampires and pirates, what is drawing kids to the series? “It’s a real adventure story. Every book is a page-turner,” Conescu says, making it a popular selection for reluctant readers. She also believes that the “strong girl characters” have won over readers. “It’s a series we really believe in. We’ve gotten great feedback from kids and librarians.” A fifth Vampirates title is slotted for U.S. publication.

Sales have been strong in the U.K., with the first title, Demons of the Ocean, selling more than 100,000 copies; the series has hit both the Guardian and British chain Waterstone’s bestseller lists. And in 2005, Waterstone’s published a report documenting the “Harry Potter” effect, which named Vampirates one of the “top 10 books for fans of Harry Potter.” Somper has received additional accolades, including the Birmingham KS3 Explores Book Award and a Solihull Children’s Book Award. He was also named “The Next Big Thing” by the Sunday Times Magazine.

Somper garnered a similarly enthusiastic reception while on a four-city U.S. tour earlier this month, to promote the fourth book in the series, Vampirates:Black Heart. “I feel like a celebrity,” he said, in response to the fans who turned out at the Texas Library Association conference on April 2, in Houston. Somper made additional stops in Philadelphia, Chicago and Cleveland, and blogged about his tour experiences on the Vampirates Web site.