Hot on the trail of the giant squid, Andrew, Judy, and Thudd smash their underwater vehicle( a.k.a the Water Bug) into Australia’s Great Barrier Reef---home to some of the world’s most dangerous creatures! Then their arch-enemy, Soggy Bob Sloggins, steals the Water Bug. The kids must find their way through the reef and get the Water Bug back---before those deadly creatures start to nibble!