Esteban is accused of a jewelry theif after someone's jewelry was stolen. Zack and Cody try to prove it wasn't him, but they end up crashing a Bar Mitzvah, for which they get punished. Meanwhile, London can't bring her dog onto her dad's ship, so Maddie takes care of Ivana (the dog) while she's gone. When Zack and Cody overhear the real thieves talking about heading up to London's suite, the twins, Esteban, and Maddie all set a trap to catch the real thieves.
Note: This is the first time we see the "S.S. Tipton" when London is on the phone with Maddie. The life preserver says "S.S. Tipton."