Super Mystery is a 36-volume series of crossover paperbacks, pairing The Hardy Boys with Nancy Drew.
The series is based on the Nancy Drew Files and the Hardy Boys Casefiles universes, as evidenced by Shock Waves, in which the melted keys from the car bombing that killed Iola Morton in the first Hardy Boys Casefile, are mentioned.
The books are written under the Keene pseudonym and are told mainly from Nancy's view.
An attraction between Frank Hardy and Nancy Drew was mentioned throughout the series.
Book #37 was written by Louise Munro Foley and had the working title The Playhouse Mystery.