Conor, Timmy, and Jack, the three members of the Freaky Joe Club, dive into their second case in Ship's Cove, Texas, when the mascot for the Octopi swim team disappears on the eve of a charity swimathon.
The Freaky Joe Club is determined that their team, the Sea Dragons, will beat the Sharks when the Imagination Railroad competition comes to the Edith R. Hammerrocker Elementary School.
A new school year presents the Freaky Joe Club with its greatest challenge, saving their school's nickname from a new principal with a mysterious aversion to hamsters.
