
Season 4 - Summary
Once again the world of "Alias" is turned topsy-turvy with the creation of "APO", a new black-ops division within the CIA. After staging her resignation from the CIA, we learn that Sydney has in fact been "recruited" into this new division. She arrives to find that Dixon, Jack and Vaughn have also been recruited, by none other than Arvin Sloane. Shocked and disgusted by the thought of working with Sloane again, she nonetheless reluctantly agrees to stay, knowing that if she is there, she can watch him, guaranteeing his capture if his loyalties are not what they claim to be.
Sloane explains that the CIA contacted him, because they wanted their own SD-6... a way to get the job done without the tangle of bureaucracy that normally hindered their efforts. Soon, it's business as usual as Syd is re-partnered with Dixon, who had voluntarily requested reassignment from "management" to field duty. We soon learn that the shocking secret Sydney had discovered at the end of the previous season was the CIA sanctioned murder of her mother... a hit carried out by her father. However, their current mission leads to the accidental discovery that Jack had assassinated Irina in order to stop a contract she'd taken out on Sydney's life.
Nadia, Syd's half-sister and Sloane's daughter, joins "APO", as do Marshall and Weiss. Working together as a team, they embark on a journey that eventually leads everyone back to Rambaldi. Along the way, we learn that Jack and Arvin have a secret agenda and have formed an alliance to achieve that end. Vaughn starts receiving clues that his father might still be alive, only to discover that it was a ploy to force him to obtain a vital piece of the Rambaldi puzzle. As they dig further, they discover that Sloane is behind this farce, and apparently was the one who ordered the hit on Sydney, framing Irina and bringing about her death. He claims innocence, and the team discovers that a man resembling Sloane has been impersonating him, going after all of the things Sloane went after in the quest for Rambaldi before his apparent reformation.
As we move rapidly into the last episodes of the season, we learn that Irina's other sister, Elena, has orchestrated all of these events in order to achieve Rambaldi's endgame. She'd spent years posing as Nadia's guardian, and uses her to gain the intel she needs to gather the remaining pieces of the puzzle. In a shocking twist, it is revealed that she'd also kidnapped Irina, orchestrating her supposed murder by Jack's hand and had been holding her hostage for almost two years, because Irina was the only one who knew how to assemble the final Rambaldi machine. As "Search & Rescue" begins, Jack, Sydney and Nadia travel to the remote jungles of Guatemala to rescue Irina.

Episode 21 - Search and Rescue
Flashback to the British Embassy in Vienna, 18 months ago: Jack goes to confront Irina about the contract he's learned she placed on Sydney's life. At first, they share a tender moment, dancing and kissing, but when she abruptly pulls away, he asks her how she could hire someone to kill her own daughter. Coldly, she replies that he wasn't supposed to find out, but that it had to be done. Jack draws his weapon and kills her. The flashback ends with Irina's lifeless body sinking down into a pool, her blood slowly swirling to the surface.
Jack and Sydney meet in the outer hallway to discuss the viability of Dixon's claim that he had seen a shackled Irina being loaded into the back of a van outside Elena's facility in Prague, prior to his confrontation with Sloane, which ended when Elena shot him in the back. Jack is open to the possibility, reminding Sydney that doubling technology existed, and while he killed a woman who looked like Irina, that may not have been the case. Sydney rejects any possibility that her mother might be alive, but Jack tells her that they will pursue every possible lead in their efforts to capture Sloane and Elena. And if her mother were out there... alive somewhere... they would find her.
Marshall is able to identify the man who had previously led the raid on the DSR facility, stealing several artifacts for Elena. His name is Lucian Nisard, and Jack instructs Marshall to log into Sloane's computer to access the Blackwell Index file on Nisard, knowing that it would have all the information the team would need to locate and blackmail him into giving them whatever information he had about Irina. Meanwhile, Vaughn notices Nadia researching her file on Martin Bishop, the man she believes killed her mother. He suggests that might not be the most productive use of her time, and tells her to talk to Jack. As Jack and Marshall access the Index and begin to download the file on Nisard, Nadia asks to speak with Jack, demanding the truth. He tells her that Bishop had not killed Irina... that he had, to save Sydney's life. She tells him that he better hope her mother is still alive and walks away.
While searching for leads, the team receives news that the Russian city of Sevogda is undergoing some crisis, but the Russian's aren't talking. A hacker friend of Marshall's sends them raw video footage that shows rioting in the streets of the city... and the camera pans upward to show them a glimpse of a huge Mueller Device hovering over the city... immediately, they realize that Elena has contaminated the water supply with properties of the Rambaldi orchid, activating the device to incite the infected citizens to turn on one another.
Jack outlines the op to find Nisard and gather intel on Irina's whereabouts, instructing Sydney and Vaughn to do whatever it takes. They travel to Ibiza and find Nisard inside a nightclub, enticing him into the bathroom, where Sydney promptly steals his PDA, tossing it to Vaughn, who uplinks to APO so that Marshall can download its contents while they coerce Nisard into answering their questions. He confirms that Irina was doubled and is still alive, and tells them that she's being held in a remote location in Guatemala. Vaughn stays to secure his extradition, and Sydney travels to Tikal to meet Jack and Nadia to mount the tactical mission to rescue her mother.
Nadia and Sydney find Irina in an underground cellar, and after a brief firefight with the guards holding her, they manage to escape, meeting Jack at a pre-determined location. Irina immediately walks over to him, and after a brief moment, punches him in the jaw for trying to kill her.
On the CIA plane back to Los Angeles, Sydney fills her in on the status of Elena's plan, informing her that Sloane is with her. Irina tells Sydney that she'd found a Rambaldi manuscript she knew Elena was searching for. In it, Rambaldi described a time when the world would be cleansed, and that when she saw what it contained, she destroyed it... which is why Elena captured her. Irina describes the torture that Elena had subjected her to while she held her captive, and she confesses that it was too much, and she'd eventually told Elena everything she wanted to know. She tells Sydney that she's sorry that she couldn't prevent what was about to happen, but that she needed her help to stop her sister. Jack protests, claiming that it was already too late for Sevogda, but Irina insists that because she helped Elena build the device, she could figure out how to destroy it... that they had no alternative. Jack agrees and orders the pilot to change course. When Irina goes to clean up, Nadia hands her a bag of clothes she'd brought along for her, and Irina recognizes her, and the two are reunited for the first time since Nadia was born.
In Los Angeles, Director Chase comes by APO looking for Jack, only to learn from Vaughn that he's heading the op to rescue Irina. She informs Langley, and their plane is immediately diverted. Irina is taken into custody, and Sydney goes to see Chase, convincing her to let Irina help them... that she's the only one who can stop her sister and Sloane. Chase agrees, and Irina is brought in to help plan and carry out the mission.
Jack, Irina, Syd, Vaughn and Nadia travel to Russia, planning to parachute into the city in hopes that they can prevent Elena from achieving her endgame. On the plane, Vaughn finally takes the plunge and asks Syd to marry him, but she assures him that they will make it out, and for him to ask her on the beach in Santa Barbara, as he'd originally planned to do.
The episode ends with the five of them free-falling out of the plane towards Sevogda.

Episode 21 - Memorable Irina Quotes
"I was pleased to get your note. This party looks insufferable."
Jack: "You broke my heart Irina."
Irina: "That was another lifetime. I won't do it again."
Jack: "Good to know."
"Jack, this is cryptic... even for you."
"S-Syd? Sydney... I knew you'd come."
"I helped Elena build the device. I can figure out how to destroy it. There are no alternatives."
"Jack, I understand why you thought you had to kill me, but the truth is... if the situation had been reversed... I would have found another way."
Irina: "And about my indiscretion with Sloane... I can only hope you'll accept my apology."
Jack: "Of all the things you've done, that's what you're going to apologize for?"
Jack: "You're going to enjoy getting to know Nadia. She's exceptional."
Irina: "I wonder where she got that from."

Episode 22 - Before the Flood
The team lands in Sevogda and moves in to rendezvous with the DSR team as planned. Jack contacts APO to find out their current status, and learns that Director Chase is in Washington trying to convince Russian officials to call off the air strikes. Marshall and Weiss decide to hack into the Russian military satellite network in an attempt to abort the strikes themselves. The team locates the DSR team's signal, only to discover they've all been murdered, except for one, who had managed to escape an attack of infected citizens. He brings them up to speed and outfits them with better weaponry, as much more force is required to take down the "zombies" than just the standard tranq gun.
The signal source for the device is a building a few miles away, and Irina explains that they must disable the device on site, because Elena had rigged it with an internal power supply. Streets are blocked due to the rioting, so their only choice is to use the underground railway system to get to the building in time.
Elena's henchman sees them and reports that they've arrived. Sloane takes a team to intercept them. Meanwhile, Marshall has been unsuccessful in hacking the Russian network, and then he remembers the Blackwell Index. He and Weiss locate the name of a Russian minister and blackmail him into giving up his access code.
As the team moves in to the subway area, Brodine, the remaining DSR agent, is murdered by one of the infected, and they must move on without him. Because the power grid has been shutdown, they have to manually rig a car to take them down the line to their destination. Working in pairs, they achieve this fairly quickly. Sydney tells Nadia that Vaughn proposed to her, and Irina tells Vaughn that she is aware of his not-so-covert activities. She advises that if he doesn't want to end up like she and Jack, he needs to come clean with Sydney. Everyone makes it into the car, but Nadia, who is attacked by a pack of the infected just as Jack gets the power going and the car begins to move. Syd is unable to reach Nadia, and she's left behind to fend for herself.
Sloane arrives at the end of the line with Elena's assault team, just as the Bristows and Vaughn arrive. He kills the team, and waits. They see him, and open the door with their weapons drawn. He tells them that he's been trying to stop Elena, but hasn't had time to figure out all of her fail-safes. They don't believe him, and Jack punches him. They contact Marshall, who tells them that Elena is actually using the Russian's network against them, uploading the same signal as the device is transmitting, and that when the Russian's scramble their planes, that signal will immediately be broadcast globally... Sloane has already told them that her men had contaminated drinking water all over the world. They have just forty minutes to stop her. Irina is confidant she knows how to disarm the device, since she was forced to help Elena build it. She demands that Sloane take her to it, which he agrees to do... and then he informs her that Elena had changed the wiring scheme, and only she knew what wire was the right one to cut. Irina makes him take her to Elena.
Meanwhile, Nadia has fought off the infected and is walking the streets, trying to contact the rest of her team. A man calls out to her and tells her he's injured his leg. Just as she tries to help, he pulls a gun... it's Elena's henchman... under orders to bring Nadia to her. He does, and when Nadia refuses to join Elena, the woman injects her with some of the infected water, turning her into one of the "zombies".
Syd heads to the roof of the building, ready to cut the wire on Irina's instruction... before she goes, she accepts Vaughn's marriage proposal, and he gives her the ring. The rest move in and take out Elena's remaining guard, taking her hostage in the process. They attempt to cut power to the device, but to no avail. On the roof, Nadia has shown up, and she and Sydney proceed to fight... Syd finally subdues her and wraps a chain around her arm to hold her still. Downstairs, Irina gives Elena one chance to tell her which wire to cut, but Elena refuses. Jack moves in to "torture" her, and she finally says Syd should cut the white wire. Irina immediately shoots her in the head and orders Sydney to cut the blue wire and run like hell. Just as Syd goes to cut said wire, Nadia wraps the chain around her neck and is choking her, when Sloane shows up and shoots his daughter to save Sydney. Vaughn arrives shortly after, and helps Sloane get a still breathing Nadia into the freight elevator, while Sydney cuts the wire and runs. They make it back to the bunker just as the water floods and destroys the building.
Later, as they wait for the chopper to arrive that will air lift them out of the city, Jack and Irina say goodbye... he lets her go, rather than force her to return to CIA custody to serve out her sentence. They share a brief kiss, and Irina turns to Sydney, reminding her to take care of Nadia and that while she may not see her on her wedding day, Irina would see her.
Back in Los Angeles, Sloane has been taken into custody. Sydney goes to see him with an update on Nadia's condition. She acknowledges what he did, and thanks him for saving her life. She's also arranged for him to visit Nadia, and the cell opens allowing him out.
Vaughn and Syd finally make that long awaited trip to Santa Barbara, discussing the idea of eloping while riding in the car. They agree to do that, but Vaughn first has to tell her the truth about something. He says it was no accident that he was the agent assigned to her when she walked into CIA Headquarters and became a double agent inside SD-6. Naturally, Syd is confused and questions him. He tells her that his name isn't really Michael Vaughn, but before he can explain, their car is sideswiped by another vehicle... and the show ends.

Episode 22 - Memorable Irina Quotes
"We like to control our own fate. You never put much faith in that, did you? Fate... destiny..."
"I just can't shake the feeling that tonight, one of my daughters will perish."
"You're not as covert as you'd like to think. Consider my life an object lesson. If you don't want to end up like Jack and me, tell Sydney the truth."
"Hello sis. Ever since you were eleven, there's something I've wanted to do... *POW*
"Listen to me... she's not your sister anymore."
"I'll give you one chance to do the right thing... not that you were ever any good at that. Which wire?"
"I'm not gonna torture you. I'm gonna let him do it, and he really doesn't care for you, especially after you tricked him into killing me. One thing you should know about Jack... he hates being anybody's puppet."
"Sydney... cut the blue wire, and then run like hell..."
"Sydney, you may not see me on your wedding day, but I'll see you."