"Magic, monsters, and mayhem abound when Percy Jackson and Annabeth Chase meet Carter and Sadie Kane for the first time in this short story collection"-- Provided by publisher.

"The Son of Sobek was first published as a short story in the paperback edition of The Son of Neptune by Rick Riordan, July 2013. The Staff of Serapis was first published as a short story in the paperback edition of The Mark of Athena by Rick Riordan, April 2014. The Crown of Ptolemy was first published as a short story in the paperback edition of The House of Hades by Rick Riordan, March 2015." The son of Sobek -- The staff of Serapis -- The crown of Ptolemy.