The FBI agents standing guard at Gui's room are as bad as Casey let on. They're talking so loud they don't hear Casey, Chuck, and Sarah, even when Chuck falls into the room from the ventilation chute. Meanwhile, a mysterious-looking guy gets out of a van with a tool belt on and enters the hotel. He sneaks into the security and surveillance room, and apparently cuts a feed to Casey's set-up in their staging room, because that screen goes fuzzy. Back in Gui's room, Chuck flashes on a wood box. Just then the mysterious van guy, now in a suit, shows up at the hotel room. The FBI guards tell him they didn't expect to se him today, and then he shoots them. Chuck, Casey and Sarah work on fleeing, considering they heard the gunshots. They barely get into the ventilation and get it closed before the guy enters the room. Chuck is not very good at the covert ops, apparently.
Back in their staging room, Casey asks if the word "silent" has a different meaning in geek that he's not aware of. Chuck apologizes for being such a loud doofus (especially since his phone rang while he was in there -- it was Morgan -- and he'd forgotten to put it on vibrate), but points out that at least he got the list. Speaking of the list, Sarah wants to just break the box open, but Chuck says it's a puzzle box and these are all him. He solves the puzzle on top of the box and it pops open, immediately shooting Casey and Sarah with something. Casey runs to get a containment unit, and Sarah and Chuck strip down to their undergarments and hop in the shower. They wash themselves and each other off. And while Chuck's washing Sarah's back, he has an almost slow-motion moment where you know he's thinking he's with the wrong girl because he loves this one more. But he doesn't have time to do or say anything because someone knocks and Sarah tells him to go answer it, because it's Casey. But, alas, it's Jill, wondering why she just caught Sarah and Chuck in their underwear, all wet and sexy. She says she knew something was up, gets teary and storms off. Chuck tries to stop her by saying he could be dying. Which would mean almost nothing to someone in this context, I'd think.