Louise and Jean Dana return to Starhurst School, which has been rebuilt after the fire described in an earlier adventure. As usual, the two sisters are eager to tackle a baffling mystery which suddenly turns up. It all starts when Professor Crandall receives an anonymous note warning him not to remove the valuable Cellini bronze fountain that he has just purchased from the old Price estate. While tracking down the writer of the threatening note, Louise and Jean courageously face danger as they become more and more deeply enmeshed in a puzzling chain of events.

A strange blond woman, phantom ice skaters, a mysterious riddle, and a terrifying gorilla-man are only a few of the clues that challenge the girls' detective skills. Louise and Jean eventually solve the mystery and finally see the beautiful fountain safely installed on the Starhurst School campus.