In book two of the Sherlock Academy series, mysteries await Rollie Wilson at the Sherlock Academy of Fine Sleuths. It has been several weeks since the evil Herr Zilch tried to steal from the academy's secret library. When Rollie finds a note from Zilch in a wastepaper basket, Headmaster Yardsly asks Rollie to help discover who Zilch's "mole" is. Rollie's Great Auntie Ei has sent him an antique newspaper from 1894 reporting on one of Sherlock Holmes's cases. What appears to be old news is actually a secret map hidden within the paper's pages. Rollie must decipher the map, then discover the Academy's secrets before the mole can hand them over to Herr Zilch. With his best friend Cecily at his side, Rollie is determined to catch the spy, all while dealing with his odious roommate, his mysterious great-aunt, and the school's new teacher.