The Time Warp Wonder (Hardy Boys Clue Book Series #8)

Detective brothers Frank and Joe work to debunk a time travel machine in the eighth book in the interactive Hardy Boys Clue Book series.

Bayport Elementary is almost ready for the annual science fair—it’s all down to the final touches. Frank and Joe have collaborated on a detective helmet. It’s the perfect lie detector—just place it on a suspect’s head and the bells and whistles will tell you when they’re lying.

But not everyone is as prepared for the big fair. Their good friend Phil has des...