S02E20: That Sinking Feeling

Phineas and Ferb build a ocean liner so that Baljeet can go on a romantic cruise with his friend Mishti, whom he now notices is a very pretty girl. Meanwhile, Doofenshmirtz wants to move all the lighthouses to the other side of town so that he can get a good night's sleep instead of hearing the constant noice from the boats surrounding the bay by his headquarters