Two years before the Blackout, Mark addresses the new class of FBI agents to the Los Angeles headquarters, and says that they will be tested and that they are people who can be counted on. Among them are Al Gough, Marcie, Janis, and Demetri. Afterward, the new agents discuss their assignments. Demetri trades partners with Al so he can work with Mark, a legend in the department. Janis and Marcie end up in Analysis, with Janis supervising her friend. Marcie isn't thrilled, and her classmates assure her that she'll soon exceed all of them.
In the present, on March 12, Mark and Demetri interrogate Marcie, the mole, and Demetri wants to know what she can tell him about his death on March 15. She claims not to know anything and Mark gets him out before he can lose complete control. He tells Demetri that there are more important answers they need, and sends him to track down their leads on Demetri's murder while he interrogates Marcie with Janis' help. The two agents listen as Marcie describes how she left stolen Mosaic information at a dead drop, after she was recruited three months before the Blackout. In her flashforward, she was able to bargain for a lighter prison sentence in return for her knowledge of the Blackout planners, and she enjoyed feeling important.
They're interrupted when Stan informs Mark that two FBI agents from Washington have arrived to take Marcie to Washington where she'll be interrogated by Director Middleton, who will use the PR for his own benefit. Mark tries to convince them to keep Marcie there for one more day but they refuse. Once they leave with the prisoner, Mark updates Stan on Dyson Frost. The fugitive scientist hasn't answered any of Mark's calls. Demetri returns to inform them that Mark's missing gun was used in a murder at a homeless shelter.
At the shelter, Mark and Demetri talk to witnesses who say that the victim, a 55-year-old homeless man, told his killer that "I knew it would be you." The killer shot the victim three times in the chest with the silenced gun and left in a 1970 blue sedan. Mark realizes that Marcie could have gotten the gun from the FBI evidence room and they go to the airport. As she's taken away, Marci admits that her employer knew that Demetri would die in L.A., and there's nothing he can do to stop his murder.
Charlie secretly sets up a play date with Dylan and both children get their parents to take them there without realizing the other will be there. As Charlie and Dylan play, Lloyd apologizes and they hear the children yell. They've bumped their heads together and Charlie is bleeding from the mouth. Lloyd manages to calm her down by distracting her, and Olivia promises that they'll still go to the school carnival.
Stan is summoned to the airport to meet with Vice President Joyce Clemente in Air Force Two. She wants to know what he knows about Jericho, and explains that the company's CEO has recently tripled his security. When Stan asks why Jericho is so important to her, Clemente explains that in her flashforward, she was President due to a political crisis that Jericho had set off, getting Segovia out of office. Stan isn't convinced, but Clemente warns him that if the flashforward comes true as seems likely, he'll do better helping her than hindering her.
At FBI headquarters, Demetri tries to trace the sedan while Stan privately asks Mark about his database investigation of Jericho. Mark tells him about Aaron and Tracy's disappearance, and feels honor bound not to discuss what he knows about Aaron and Jericho. Stan asks to talk to Aaron and Mark agrees, but warns that he doesn't know how to find Aaron since he went off the grid.
The agents get word that the LAPD are chasing the suspected killer, Ross Weber, who is driving a blue sedan. They go to the office building where the police have cornered the killer, who has taken hostages. Mark goes in and Demetri insists on accompanying him, despite the fact the killer has Mark's gun and could kill him. Mark notes that Demetri could be shot now and die in three days, but Demetri insists. The demented Weber demands to see Randy Savage and accuses his hostage of causing the Blackout. Demetri distracts the man while Mark circles above and around. As Demetri walks toward Weber, the agent disarms himself and tries to calm him down. As Weber hesitates, Demetri gets close enough to draw a hidden gun and shoot Weber in the shoulder, disarming him.
As the EMTs take Weber to the hospital, Demetri confirms that Weber doesn't have Mark's gun. Mark wonders why Demetri put himself at risk, and Demetri reminds him of his speech. Demetri admits that he doesn't feel like someone who could be counted on since he came to realize he was dying on March 15. He asks Mark for help and Mark points out that he hasn't had much luck in relationships, but tells his partner to take Zoey somewhere safe and leave for a few days.
Two years ago, Demetri testified in a case where Zoey was the defense lawyer. After demolishing his testimony in court, Zoey asks him out to dinner afterward. Now, Demetri enjoys dinner with Zoey and explains that he was only testifying in the case where they met because he switched partners with Gough. He talks about how small, seemingly random decisions added up to something good, and then asks Zoey to marry him right now and then leave on an extended Hollywood. Zoey quickly agrees.
Olivia visits Lloyd at home to thank him for helping Charlie earlier. He invites her in and she initially agrees, but then says that she should go. Olivia admits that she made a mess of things, and Lloyd explains that he did the same thing, using Dylan's autism to force a separation with his wife. However, Lloyd suggests that in their flashforward, they are together for a reason. They admit that they're scared but then kiss.
Aaron returns to his cheap hotel room and finds Stan waiting for him. Stan explains that he managed to trace Aaron through his Internet searches about Jericho on a nearby library computer, and then checked all the cash-only hotels. When he explains that he's a friend of Mark and needs proof against Jericho, Aaron tells him that he's sure Tracy is alive in Afghanistan. He admits he planned on going using his passport, and Stan warns him that Jericho will quickly find and kill him. He offers to help Aaron get to Afghanistan safely, but in return he wants Aaron to convince Tracy to testify against Jericho and their destruction of the village.
The agents take Demetri out drinking to celebrate his wedding the next day. Janis finally takes him out to find him a taxi.
Stan arranges a meeting with Aaron and explains that he's set him up with a military cover as a power technician. He provides Aaron with a cell phone so he can capture video of Tracy testifying and upload it via satellite. Finally, he explains Aaron's escape route and provides him with several untraceable guns. Stan wishes him well but figures he won't be coming back, but Aaron is confident that what he saw in his flashforward will come true and he'll be reunited with Tracy... and he'll kill anyone who tries to stop him.
As Janis takes Demetri to the cab, he asks if she thinks he's a coward. She assures him he's doing what he has to. As the cab starts to pull away, Demetri asks her about the night they spent together in Somalia, and she tells him that she's now pregnant before walking away.
The next day, Demetri and Zoey go to the church they've selected for their wedding. The reverend won't officiate at their wedding without having seen them in pre-marital counseling. On the balcony above, Dyson Frost secretly watches them.
At the FBI office, Stan lies and tells Mark he never found Aaron. Vreede informs them that he's traced Frost's cell phone to a convenience store 12 days ago. On the surveillance footage, they see Frost driving a blue sedan, and Mark figures that he has some kind of secret plan.
At home, Demetri is dressing for his wedding when Frost knocks him out.
At the church, Internet minister Vreede is ready to marry Zoey and Demetri. Demetri doesn't arrive and Mark tries to contact him as Zoey worries.
That night, Frost is parked in a street. He checks on the unconscious Demetri in the back and then gets out and walks away.
Olivia is running the school's Wheel of Fortune booth when Mark calls to tell her he can't get there because of Demetri's disappearance. He tells her to be careful and after he hangs up, Olivia realizes that Charlie has wandered away.
Charlie is sitting on a bench at the carnival. Dyson Frost sits next to her and says hello to her by name.