In Havana, disguised as a dancer, Sydney meets an informant, who says that the Third Faction is planning a large-scale attack on a civilian target. He gives directions to a locker in LA from which Dixon retrieves a hard drive that has the details. Unfortunately, Ulrich, the informant's boss, watches the exchange, and later, his men ambush Sydney. Ulrich shoots the informant before saying that he has something worse for her. At APO, when the hard drive is connected to the network, it explodes and releases a chemical agent. The building's security system reacts to remove the vapor, and the complex goes into lockdown. Sloane calls Marshall, who is in the parking garage, having arrived late for work thanks to a small crisis at home. Marshall checks the firewall networks and reports that they are secure. Vaughn calls to see if Sydney made her flight; the ringing phone awakens Syd, who finds herself in a coffin, buried alive with the body of the informant. The others explain that they're locked in for the next 36 hours. Listening to the call, Marshall volunteers to go get her, explaining that he can build a device to track the frequency of her cell phone. While Marshall works to find her, Syd transmits a picture of the informant to APO so they can search for his partners in crime. She weakly repeats herself, and the others realize that she's fading fast. Jack calls Marshall, who has located the cemetery. However, it's huge, and Sydney's phone battery dies. Marshall tells Vaughn how to access a satellite over him, and they find Sydney via thermal imagery. Marshall digs and reaches the coffin, but Syd isn't breathing. He uses CPR to revive her, as the others at APO watch the satellite transmission. A bit later, Sloane sends information about Ulrich; they still need to find the target of his attack plans. Since Ulrich knows Sydney, she suggests that Marshall go in. They travel to Berlin, where Syd coaches Marshall. With Sydney listening on comms, Marshall obtains an audience with Ulrich and introduces himself as Jack Bristow. He is able to surreptitiously transmit the data on Ulrich's computer to APO, but Vaughn radios that the data is encrypted. To decrypt it, they'll need the computer in the basement, that is protected by a retinal scanner. Marshall tries to force Ulrich to the basement using his cell phone gun, but the gun accidentally goes off and kills Ulrich. Jack talks Marshall through cutting out Ulrich's eye. Sydney defeats Ulrich's guards to join Marshall, and they go to decrypt the data, using the eye to access the computer. The target of the attack is revealed: Hong Kong. Vaughn informs the CIA, and the attack is thwarted. Back in LA, Sloane says that the Third Faction extends far beyond what they thought, and APO will need to confirm hundreds of names listed as contacts. Sydney drives Marshall home; he says that he hates to lie to his wife, but he understands that it's part of the job. Sydney goes to wait at the train station. When the lockdown is over, Vaughn meets her, and they share a dance.
Informant: You dance like an angel.
Sydney: Yet my feet touch the ground.
Sydney: Do you have any idea how hard it is to maintain cover while dancing the salsa in three-inch heels?
Vaughn: Yes, actually I do, but let's keep that between us.
Sydney: You hate to dance.
Vaughn: How do you know?
Sydney: I've never seen you dance.
Vaughn: Well, I'm a mysterious man; there are a lot of things you don't know about me.
Sydney: You've never once taken me dancing.
Vaughn: Okay, let's go dancing.
Sydney: But you hate dancing.
Vaughn: And yet, I'm taking you. Like I said, I'm very mysterious.
Ulrich: I need them to see what I do to my enemies. I need them to see what I do to you.
Sydney: So, would it help in your demonstration if I started crying and pleading for my life?
Ulrich: You obviously don't understand your situation. [He gestures to the man he just shot.] He was my friend. You're not.
Sloane: Third Faction wants us on our heels. They think they can bomb our operation; they think they can bury our agents alive. And they think that will stop us. Well, they're wrong. We have a job to do. Get to work.
"Okay, that can't be regular Spanish - that's way too fast." Marshall, experiencing the language barrier
Jack (on the phone): What's your status?
Marshall: Well, it's really hot here, and everyone keeps calling me Chango.
Sydney: Make eye contact with everyone, particularly Ulrich's bodyguards.
Sydney: You have to convince them that you're not scared.
Marshall: Right . . . Yeah, I think you're supposed to do that in prison too, I heard.
Marshall: This guy, he buried you alive.
Sydney: Yeah, but he cheated - he hit me with a car first.
Sydney: Be careful when you load it.
Marshall: Syd, I know, I built that, remember? I mean, I built all that stuff.
Sydney: It's different in the field.
"Hush little Mitchell, don't you cry. Daddy's here to teach you 'bout lanthanides..." Marshall, beginning a soothing yet educational lullaby for his son
Sydney (on comms): What do you see?
Marshall: Well, a lot of people who are into spanking, apparently.
"Not really a policy, per se. More of a been-burned-by-too-many-fly-by-night-terrorists-to-trust-them sort of thing. You know, one day they say, 'We'll pay gold,' the next they say, 'Did we say gold? We meant goats--'" Marshall, rambling to buy time
Marshall: I got a . . . spork.
Jack: What's a spork?
Marshall: I didn't save the world exactly. Just Hong Kong.
Sydney: You saved me.
Marshall: Well . . . all in a day's work.
* This episode was definitely not for the squeamish. Or the claustrophobic.
* Jack's thorough knowledge of the eye is disturbing, yet not at all surprising.
* I'll never look at a spork the same way again.
* As soon as that character we've never seen started working with the hard drive, we knew that he was doomed.
* It's a bit odd that the bad guys left Sydney's cell phone with her, but then again, they probably thought that there was no one that could help her.
* I loved the team's concern for Sydney, especially the shot of Jack watching the satellite image of Marshall digging.
* I also loved Marshall: Marshall at home, Marshall talking to his son, Marshall getting kissed at that club, and - perhaps most of all - Marshall posing as Jack.
* Did Marshall repeat the line that Sydney gave him, or does he really speak German?
* The way the camera panned down to show the metal rod that Marshall used against Ulrich's guard, I have a feeling that is going to come back to haunt him.