"Atlantis" is the 36th episode of Phineas and Ferb. During a trip to the beach, Phineas, Ferb, Isabella, Buford, Baljeet and Irving try to find the lost city of Atlantis which is located in the bottom of the ocean. Then Candace and Linda enter a sandcastle building contest when Candace finds out that Jeremy is the judge. Meanwhile, Doofenshmirtz creates an army of plants.