To celebrate Owen coming home, Katie invites Corey, Tuesday, Roger and Patty to a beach party cookout. An overly cheerful customer buys some musical soundtrack LPs from Permanent Record, and bugs Margaret with her cheeriness. When Tuesday's roommate moves out and she starts looking for a new one, Corey seriously considers shacking up. But Roger doesn't think it's a good idea for Corey to take things this fast with Tuesday. Besides, he's got it made at RT's. Sophia is no happy camper when the sultry and mysterious Cossima Blair shows up at RT's company, Videx, to try to sweettalk him into merging with her company, BuffCo. Sophia tries to warn RT that Cossima and BuffCo are bad news, but RT already knows that... and doesn't care. Certainly not after she puts the moves on him at dinner. The showtunes fan returns to Permanent Record to attempt to return a warped copy of "Carousel." When Margaret points to her "No refunds, no exchanges" sign and tells her to get out, the customer refuses to leave and becomes progressively less cheery. Corey tells Tuesday that he wants to be her roommate, and she likes the idea. Roger, on the other hand, is angry and feels betrayed that Corey has decided to "leave" him and his dream of sharing a swinging bachelor pad. When the kids all get to the beach late at night, they find out Katie lied to them. She wants them to pick up garbage for a school project. Corey, Tuesday, Roger and Patty in turn lie to Katie and Owen and pretend to be cleaning up while they're doing all the work. RT falls for Cossima's charms and tells Sophia he's agreed to the merger -- and Sophia figures out that they slept together. After Sophia finds Cossima, now co-president, sitting in RT's chair, the two women get into a catfight, which Sophia pretends is a make-out session after she sees RT walk in. Mistakenly thinking Sophia stole Cossima away from him, RT rips up the merger contract and kicks Cossima out. Corey patches things up with Roger by telling him that he can rub his dream bachelor pad in his face when he gets it. Katie ditches Owen and gets plastered with the others. The showtunes fan plays mindgames with Margaret, eventually causing her to crack and admit that her records are her "friends" and she's a bully because the store is the only place where she's in control. Margaret admits she was wrong and plans to cough up the refund, but the woman turns it down, announcing that her work is done. And Margaret goes right back to her old ways for the next customer. While talking to Katie and Patty, Corey and Tuesday both have second thoughts -- which are squashed the instant that Tuesday tells Corey that she loves him. And the show ends with the two lovebirds kissing on the beach.