The episode begins with Becca being brought to the CIA substation. Jamie asks Dax too stay away from Becca’s interrogation, as he is too close. Martin wants Jamie to track the train Michael is on and Jamie gives the orders. Next, Jamie goes into the room and Becca wants to know as to why she is being kept there and why isn’t the CIA looking for her son. Jamie tells her that they think that she is lying as they found three sets of prints on the certificates. She then moves on to talking about an operation Becca was involved in; operation songbird. Becca says that songbird doesn’t have anything to do with this case. But Jamie points outs the parallels. Becca recalls when Martin first gave her the case.
It was a case, where the wife knew secrets about her husband, who was brutalizing her. She wouldn’t speak until she gets her son. She had left two years ago; but now she won’t testify until she gets her son. Paul and Becca had decided not to work together for Michael’s safety. But this case demanded them to. Next, Michael and Oksana are on the train and it is time for Oksana to take her insulin. But they have just one and that won’t last long enough. Meanwhile, Giancarlo talks to Dax. Dax tells him that Becca made them land in the middle of something huge and that Giancarlo is blind that he cannot see what Becca is doing. Dax tells him that if e wants help, then he should be given the complete backing of the Interpol; and all authorities. Giancarlo agrees.
Dax adds that Azimoff is not the head of anything and he is working for someone else; someone worse; maybe an unknown ex-operative who they call suspect zero. The suspect zero is very private and no one would know about him or her; for instance someone who has been dead for years. Giancarlo is obviously reminded of Paul and Dax tells him that there is no way that Becca is unaware of what is happening. Alongside, Jamie tells Becca that, operation songbird ended the way it did as Paul and Becca were working on the other side. Becca tells her that if she proves her innocence, then the CIA will use its full resources to find her child; and if otherwise then she would go back. Next, on the train, Michael is deciding to jump off the train as they need to get insulin for Oksana.
He realizes that it is a freight train and may not stop for days. He climbs on to the roof of the train to go to the driver or a phone. But just then he sees the guard from the mansion. At the CIA substation, the team tracks down the train, at it would arrive at Bratislava in two hours. Meanwhile, Martin is talking to Fitzpatrick and Violet. He tells them that Paul and Becca would never let their emotions mixed up in a case; but songbird was different for them. Jamie is still finding it to believe that Becca couldn’t read her husband. Next, we are taken to the flashback, where operation songbird is set in motion; Becca is talking to the mother. She tells Becca that her husband had told her that she will never see her son, Maxim, again.
The mother sees Maxim but she can’t meet him because of her husband’s bodyguards. Becca assures her that Paul and she will take care of Maxim. Becca is dressed as a volunteer and when Maxim goes to her to return his coat; she gives him a necklace that his mother had given for him. Becca tells Maxim that his mother wants him to live with her. And maxim tells her that he too wants to be with his mother. Becca wants Maxim to go to the men’s room where Paul would help him. Next, on the train, Michael tells Oksana about the guard and she is ready to shoot the guard. The guard arrives on the top of the bogie they are in and lifts the lid and peeps inside. But both of them are hiding. The guard leaves. But on his way back, he finds evidence that Michael is in that bogie. He gets inside and finds them.
A fight ensues; but both of them are no match for the guard. But in a while they manage to throw him off the train. But in moments the train stops and they are not far away from the guard. They see the guard trying to get up. They get out of the train and run. Next, Jamie thinks that Becca was in the men’s room when Paul was talking to Maxim; but she says that wasn’t. Jamie feels that in that case Paul must have lied to her about what happened in there. In the flashback, we see that Maxim is talking to Paul and Paul asks Maxim to change his clothes. Maxim goes in to change and locks the door behind him. Cut to the present, Becca recalls that the father’s name was Gregor Novovski, which they thought is a cover name.
Jamie shows her a photograph; and it turns out that Maxim was Azimoff’s son. Becca is shocked and tells her that she has had no connection with him for the past ten years; the CIA had her under surveillance and that they can’t prove it either. Jamie then tells Becca the money Becca got of the life insurance, was wired from an account in Zurich and that the life insurance settlement was fake. Becca doesn’t know what to say and Jamie says that Azimoff paid her for a job well done. Becca denies, and she continues about the songbird operation. In the flashback we see, that while Maxim is in the men’s room, the guards are waiting outside. But Becca manages to throw them down to the ground and all three escape.
But as they are about to leave, a car drives in and they start firing at their car. But Paul manages to trick them and they are safe. But then immediately we see a white van with Wien Net painted on it following Paul’s car. Maxim was having second thoughts about the whole thing. But Paul convinces him to go along with the plan. They arrive at a park, where Martin is waiting with Maxim’s mother. She was happy to see Maxim. As they were walking towards each other, Maxim pulls out the gun from Paul and shoots his mother. Becca is shocked at what just happened. Maxim then drops the gun and runs into the white van that was waiting for him. Cut to the present, Jamie asks her as to why didn’t she drop Maxim.
But Becca tells her that she could never shoot a 12 year old child. Becca tells her that she hasn’t seen Maxim after that incident. Jamie knows where Maxim is; he is the sharp shooter with Azimoff. Meanwhile, Dax and Giancarlo stop the train. But they don’t find Michael. Giancarlo is now losing his faith in Becca and Dax tells him that Becca always manipulated him. Michael and Oksana are in a small cellar in a vineyard. Oksana needs her insulin. The guard finds them once again; but once again Michael manages to beat him down and this time he is dead. Jamie tells Becca that Michael wasn’t on the train and now no one believes Becca. Jamie tells Martin that she wants access to the redacted files of Paul. They are on the verge of finding suspect zero. Meanwhile, in the interrogation room, a secret door opens mysteriously, and Becca escapes through it.
Jamie walks in and is surprised to find Becca gone. Just then someone holds her from behind and stabs her; its Violet! Violet leaves from the scene and now Becca gets framed for Jamie’s murder. Becca is out on the streets. Dax arrives at the murder scene with Giancarlo. Now everyone thinks that Becca was lying all through. Next, Michael is carrying Oksana to some place where they can find insulin. Oksana is in a bad shape. Becca is walking on the streets of Vienna and we are taken to the flashback, where Paul tells Becca that they are not responsible for this. Becca tells him that she does want to fail as a mother. Cut to the present, Becca is still walking but this time we see Maxim following her. The episode ends.