ABC is reaching way back into the history of mass media to promote the second season of "Castle."

The show, about mystery novelist-turned-NYPD consultant Rick Castle (Nathan Fillion), will hype the new season with a staple of 19th- and early 20th-century newspapers and magazines: a serialized novel. Chapters of the book will appear online starting in August, according to The Hollywood Reporter, and fans will be able to buy the book in late September.

The novel is called "Heat Wave," and author "Richard Castle" will post a chapter a week on ABC.com starting Monday, Aug. 10. The second season premieres Monday, Sept. 21, and the full novel will hit bookstores the following week.

"Heat Wave" will feature a few elements that will be familiar to fans of the show, but it will primarily be a stand-alone mystery.

"Castle" already has some mystery-novelist cred in hand, having featured authors James Patterson and Stephen J. Cannell as Castle's poker buddies in the pilot. The network isn't revealing the true identity of the "Heat Wave" writer.

Repeats of "Castle" will air on Saturday nights in July starting this week.