▁spell ▁on ▁Mel ody ▁we ars ▁off , ▁causing ▁her ▁to ▁revert ▁into ▁a ▁human ▁and ▁nearly ▁d rown . ▁T ip ▁and ▁D ash ▁defeat ▁Und ert ow ▁by ▁having ▁him ▁sm ash ▁through ▁the ▁layer ▁of ▁ice ▁covering ▁the ▁entrance ▁to ▁Mel ody ' s ▁cave ▁and ▁crash ▁straight ▁into ▁the ▁solid ▁rock ▁wall ▁behind ▁it , ▁knock ing ▁him ▁un cons cious ▁and ▁causing ▁all ▁of ▁his ▁teeth ▁to ▁sh atter ▁and ▁fall ▁out . ▁After wards ▁they ▁grab ▁Mel ody ▁and ▁drag ▁her ▁to ▁the ▁shore , ▁saving ▁her . ▁Mel ody ▁then ▁man ages ▁to ▁get ▁hold ▁of ▁the ▁tr ident ▁and ▁throw ▁it ▁back ▁to ▁T rit on , ▁who ▁enc ases ▁M org ana ▁in ▁a ▁block ▁of ▁ice , ▁which ▁s inks ▁under water ▁along ▁with ▁a ▁picture ▁of ▁Urs ula . ▁ ▁Mel ody ▁reun ites ▁with ▁her ▁family , ▁Eric ▁and ▁A riel ▁apolog ize ▁to ▁Mel ody ▁for ▁not ▁telling ▁her ▁the ▁truth ▁years ▁earlier , ▁and ▁T rit on ▁offers ▁his ▁grand d augh ter ▁the ▁choice ▁of ▁becoming ▁a ▁mer ma id ▁perman ently . ▁Instead , ▁Mel ody ▁uses ▁the ▁tr ident ▁to ▁dis integr ate ▁the ▁wall ▁separ ating ▁her ▁home ▁from ▁the ▁sea , ▁re unit ing ▁the ▁humans ▁and ▁the ▁mer people . ▁ ▁Cast ▁ ▁T ara ▁Str ong ▁as ▁Mel ody ▁ ▁J odi ▁B enson ▁as ▁A riel ▁ ▁Samuel ▁E . ▁Wright ▁as ▁Sebastian ▁ ▁Pat ▁Car roll ▁as ▁M org ana