Justin Sanders is back, sleuthing with best friend Eric. Together, they are solving the mystery of the Pickerel Lake monster fish and Cousin Randy's murder even as the risks escalate ever higher. When escaped juvenile prisoner Gusta and his accomplices zero in for revenge, it's up to Justin and Eric to take advantage of new clues and their investigative skills to uncover the dark secrets before it is too late. The suspense builds as the killers surprise the kid detectives and their girlfriends on a picnic and tie them up, leaving them to be devoured by wild animals in the Minnesota woods. Can they escape in time to save themselves and foil their adversaries' plan of capturing the monster fish and transporting it to a secret location?