As a child he was an avid reader of SF novels, in particular Nerawareta Gakuen, but in high school he became more interested in films after watching The Terminator.
After graduating from Waseda University he worked for three years as an assistant director for a television production company.
In 2003 his original screenplay won the "Kido Award" sponsored by the Motion Picture Producers Association of Japan to train and educate new screenwriters.
In 2007 he made his debut as a fiction writer by turning his winning script into the historical novel Nobō no Shiro (のぼうの城, "Floating Castle") which sold over two million copies.
In 2013 Wada published the two-volume historical novel Murakami Kaizoku no Musume (村上海賊の娘, "The Murakami Pirate’s Daughter"), which garnered both the Booksellers Award[2] and the Yoshikawa Eiji Prize for historical fiction[1] and quickly became a bestseller.