The Suite Life on Deck

London, Zack, Cody and Mr. Moseby set sail on the S.S. Tipton for their semester at sea. London convinces her roomate to leave the ship so she can have a room to herself. Cody finds himself sharing a room with Woody, who is very messy, and Zack shares a room with Bailey, who is a neat freak. Nobody knows that Bailey is a girl who disguised herself as a boy in order to gain a position on the ship after she found that there were no more vacancies for girls. Zack and Cody agree to switch roommates, but Zack changes his mind after he finds out that Bailey is a girl. After everyone else eventually finds this out Bailey is allowed to stay, filling the position vacated by London's ex-roommate, and Bailey becomes London's new roommate. This is the last straw for London and she escapes to Parrot Island via helicopter.

When the S.S. Tipton makes a special trip to pick up London from Parrot Island, Bailey, Moseby and Woody find themselves in jail because all the parrots left for Seal Island after Tipton Industries cut down all the trees. It's up to Zack and Cody to get them out of it but Zack and Cody end up in jail along with the others, and Bailey has to use her pig, Porkers, to rescue them. Zack and Cody fight for Bailey and Zack lets Cody have her after finding out about her ex-boyfriend Moose and seeing she has too much "baggage".

Bailey is mad that London is hogging all the space in their cabin, so she makes up a "Sea Snark" attack, but later feels guilty and tells her the truth. Meanwhile, when Zack uses up both his and Cody's meal cards buying things for all of the girls on the ship, they go broke. To make up for it, Moseby puts them to work. Because of that, Zack thinks that Cody should win the yo-yo contest for its $1,000 prize, but Cody finds himself up against the pro, Johan Yo.

Zack has a crush on a cute passenger named Violet, but must deal with her wealthy "boyfriend" Ashton and snooty mother who will do anything to keep Zack and Violet apart. Meanwhile, Cody referees an intelligence test between London's dog Ivana and Bailey's pet pig Porkers. The episode includes plot elements from the 1997 film Titanic, where Jack was framed for stealing the "Heart of the Ocean" necklace.

London and Bailey are on a mission to prove that Miss Tutweiller is dating Mr. Moseby after overhearing a conversation between the two. Meanwhile, Zack convinces Cody to sneak out after curfew to catch the Starlight Follies show on the ship. When they finally make it past the security guard and into the show, they become convinced that their teacher, Miss Tutweiller, is one of the showgirls by seeing her heart shaped anklet in the show, and during class, so Zack sends Bailey and London undercover as two showgirls to find out.

The ship is struck by lightning when it crosses the International Dateline, which places Cody in the same day over and over. He tries to use each day as a chance to let Bailey know how he feels about her, but something gets in the way every time. It's then up to Cody to divert the ship from the lightning to set them back on the right course.

The S.S. Tipton visits Greece. While they are there, Bailey crushes on the tour guide, which makes Cody jealous. To impress her, Arwin's cousin, Milos, gives him a replica of the ancient amulet of the Greek goddess Aphrodite to give as a gift to her, but in a mix up, he ends up getting the real one. Meanwhile, London has to write a speech for her father, who is funding a new exhibit, but finds it very difficult, but then has a dream about Greek history, which inspires her.

The class has a school project to complete and Cody chooses Bailey to be his partner, disappointing Zack who had hoped to get Cody to complete his and Woody's project for them. After Bailey tells London that she has partnered with Cody, London teams up with Zack and Woody. Cody is trying to catch a famous sea monster, but keeps failing and disappointing Bailey. Zack tries to sabotage Cody's project. However, his own project turns into a monster when London pours a smoothie into their plant project, causing it to grow and eventually trapping Zack, Woody, and London. The sea monster shows up at the end of the episode.

Chelsea, Barbara, and Bob visit the S.S Tipton. Cody is worried about how he's going to tell Barbara about his feelings for Bailey, but Barbara has to dump Cody because she and Bob are now dating. Right before Cody tells her about Bailey, Barbara tells him about her and Bob. To make Barbara jealous, Cody tells her that he and Bailey are also dating, thinking he can get away with the lie because Bailey is off the ship, but she returns early. London tells Chelsea that her room is her shoe closet, and that Woody is her servant. Woody agrees to help her because he has a crush on Chelsea. During movie night, Cody tries to make Barbara think that he and Bailey are dating, but Bailey eventually finds out. Cody apologizes and Bailey forgives him and says if he wanted her to be his pretend girlfriend, all he had to do is ask. To show it, she tickles him, wraps her arms around him, and finishes with a kiss on the cheek (causing Cody to faint) saying that would have made Barbara really jealous. Chelsea finds out that London is just a regular student, but instead of telling everyone, tells London she will tell everyone that London was "abducted by aliens" instead.

When Cody and Kirby don't allow Zack to bungee-jump off the side of the ship, the brothers accidentally knock Kirby off the ship, but Kirby lands in the hot tub. To make it up to him, Zack and Cody tutor Kirby so he can pass his high school equivalency exam to earn a better job. Meanwhile, London embarrasses Bailey on her internet show in a new segment called "Boo You!"