The Three Investigators Series By Robert Arthur – Silver Dagger Book Tours. Genre: Middle Grade Mysteries with a Supernatural hook. The motto
of The Three Investigators is “We Investigate Anything,” and their trademark is “???” – three question marks, taken together.

On the 60th anniversary of the creation of The Three Investigators series, the first-ever English-language e-book editions of Robert Arthur’s novels, as well as the first new
English-language print editions in over twenty-five years, stand ready to delight a whole new audience. Be sure to seek out all ten titles! Read Guest Post and Enter Giveaway.