III, Morgan, III Charles E. Morgan 
Case of the Templar’s Sword [EPUB ebook] 

In "The Case of the Templar’s Sword, " Brains Benton (Operative X) and Jimmy Carson (Operative Three) find themselves up to their eyeballs in mystery. A house appears to be haunted and it gets broken into. However, nothing was taken! What were they looking for? The firm of Benton and Carson flies into high gear and uses all of their resources to try and figure things out. That includes using their new hydrofoil speedboat and going on a perilous journey underneath a mountain of rock! Join our daring operatives in their latest adventure of chills and spills!