The Hardy Boys Undercover Brothers

The Undercover Brothers series debuted in 2005 and ended in 2012. It was written in a first person perspective, alternating between Frank and Joe each chapter. It featured the all-new ATAC (American Teens Against Crime) organization which was partially founded by their father, Fenton Hardy, but which their mother, Laura Hardy, did not know existed. They own and ride motorcycles in this series rather than a car or van from the previous series.

This series had several spin-off and related series including a couple series of graphic novels, a yearly Nancy Drew Super Mystery crossover series, three one-off specials, and a couple computer games.