Sarah storms out of the room, and Chuck follows, trying to be upbeat about this all. But Sarah says when she found a tracking device in Zondra's boot, they were on a mission to nail Gaez. Chuck asks if Sarah really thinks Zondra's working for Gaez after she was cleared by the government. Sarah says we'll see. Then Gaez, in a bar, gets a voice-encoded call that tells him they're on their way to Rio. Gaez is happy their plan's working so perfectly.

Amy -- a total ditz -- is so excited about going a mission together! She wants high-fives, but no one gives her one. Chuck pulls Sarah aside and says he has an idea: He'll be stuck in the van with Casey so will have plenty of time to review all the CIA files on Gaez and the Cat squad. He says they can take down Zondra with Gaez if she's a double agent, but if not, Sarah can re-engage with her past, which is so much bigger than their engagement party. Sarah reluctantly agrees. Zondra pipes up she can see the hamster wheel turning in Sarah's head and tells her to keep her paws off her boot. Sarah spins around and gets in her face. Casey tells the Cats to cool it. Then he instructs Morgan on taking care of Carina while the rest of them are gone. Morgan protests he can't be left alone here with that woman, who wants him badly. Casey is as skeptical as you might expect.

Carina gets intel on Gaez's party and lets them all know where he'll be. Zondra wonders how they should breach community: disguise or commando entry. Amy gives them a "duh," since it's a party. Covert not necessary. Cut to Carnival in Brazil. The three Cats are all wearing white and looking smokin'. Zondra wants to split up and cover more ground, even though Sarah's not comfortable with that. Zondra (the bitch, remember?) doesn't really care what Sarah thinks. Sarah and Amy stick together, although Amy lingers a little behind and dances happily. Sarah's necklace cam relays the party back to Casey in the van while Chuck goes over the files to figure out if Zondra's a traitor. Casey tells Chuck that it must be nice to want to fix everything, but he's not like that. Apropos of nothing, he says Grimes told him to meet Alex's mom and he was going to, but then let it lie. Back inside, the girls spot Gaez, and want to get the layout of the place from Chuck and Casey.

Morgan and Carina bicker back at Castle, mostly about Alex. Carina assumes Morgan told her he loves her, but of course he hasn't. He says he was going to until her father was thrown from a roof. Anyway, he plans to soon. But Carina thinks it's not even serious. Morgan gets a call from Alex, who's at the Buy More, but Carina won't let him go, even going so far as to block him in with his cane. She tells him to take it up with General Redhead. So Morgan answers his phone and tells Alex he was shanghaied into babysitting an injured agent so he won't be able to make their lunch date. Carina feels Morgan up while he talks to Alex, who is pissed but just says Morgan owes her. He promises to make it up and ends the call with a bunch of kisses. Which is the perfect cue for General Redhead to come in and make fun of him, then tell him about a problem in Rio.