when phineas and ferb accidently use their shrink way on christmas eve in bud's pet store and they all become fishes [except perry]and they meet milo and oscar and fish phineas asks if their is a way out but milo and oscar tells the new fish group that the only way out and back to the shrinking device is to have the water fuels like milo did but he still does have in his and oscar's room but while they are hurrying they come across a group of secret fishes in robes who tell the phineas and ferb fish they are needed and they start running away but the secret fishes get them.