Noah’sarkdriftsontheopenseas,withbestfriendsFinnyandLeahonboard.But,afterweekswithnolandinsight,foodstocksarerunninglow.Thefragilepeacebetweencarnivoresandherbivoresuldbreakanysend.Afteraseriesofunfortunateevents,thekidsfindthemselvesinadvertentlywashedoverboard-alongwiththelastofthefoodsupplies.Leahandfellowcastaway,theirnewfriendJelly,aremaroonedonaremoteisland.WhileFinnywakesinastrangelonyfilledwithoddlyfamiliarcreatureslivinginharmony-underthethreatofamenacingvolcano.Inaraceagainsttime,tideandterrifyingtremors,Finnymustrescuehisfriends,reunitewithhisfamilyandsaveawholelonyfromtotaldestruction.