The terrorists responsible for the bombing of Grand Central Station finally reveal themselves, but instead of answers, more questions remain. While back at Quantico, the recruits receive a well-deserved few days off for the holidays, but not everyone is oh so merry when secrets are revealed and lines and blurred.

Alex finds herself in the middle of a congressional hearing to testify about the terrorist bombings. Convinced Elias didn’t act alone, she is determined to find answers and the truth. While back at Quantico, a new group of NATS join Alex and her classmates, causing tension and competition between the groups of trainees.

A terror cell tries to infiltrate Quantico, forcing Miranda and Liam to pay a deadly price. While in the future, Alex continues to get instructions from the terrorist – only this time, it’s Claire Haas’ life that hangs in the balance.

At Quantico, the NATS are given a training exercise that hits too close to home for Shelby. While in the future, Alex finds an unlikely ally in Hannah, as she continues to try and stop the terrorist from striking again.

At Quantico, the NATs look into each other’s background to determine who gets high-level security clearance, and in the process Alex, Shelby and Iris learn some surprising truths about Drew, Will and Caleb. Meanwhile, in the future, Alex contacts Claire Haas (guest star Marcia Cross) in order to find her missing friends and is shocked when she discovers what happened to Cale.

The NATS are excited that graduation is near as they prepare to leave Quantico and head out into the real world for their new assignments. In the future, Alex learns someone she cared about at Quantico is not who they seemed to be, as she finds herself at the heart of another possible attack.

It’s graduation day for the NATS of Quantico, while, in the future, Alex and her team find themselves head-to-head with the terrorist.

At the Farm, Owen teaches the trainees about enhanced interrogation techniques, and turns the tables on his students by putting himself in the hot seat. Meanwhile, Shelby goes undercover. In the future, a new president is sworn in, and Miranda makes a tough choice.

At the Farm, Owen teaches the recruits a lesson on the necessity of betrayal, with a mission of getting the Venezuelan Consul Gabriel Carrera to turn on his country. In the future, Alex is forced to team up with Miranda in order to save the hostages, while President Claire Haas has a plan to end the crisis once and for all.

Alex tries to convince Owen of the traitor amongst them. The recruits are tasked with getting an asset out of Germany – but their target has a death wish. In the future, the terrorists resort to new means to gain information from the hostages.

The recruits learn how to burn everything down if they are ever exposed. Meanwhile, a mysterious death leads to an FBI investigation at the Farm. In the future, Alex heads back into the crisis zone and exposes the true traitor within the CIA.

In the wake of the G20 hostage crisis, President Claire Haas assembles an illegal and clandestine joint task force, bringing together Alex and her friends from both the FBI and CIA to unmask a global conspiracy.

A despondent Clay meets with the President to discuss the future of the task force, but he’s interrupted by the arrival of his brother. Meanwhile, Alex leads an operation to expose the collaborators’ plans to sink the President’s reputation, and she teaches Owen to trust his instincts.

With all the collaborators unveiled, the team uses Clay and Maxine’s engagement party to entice them into one place. The mission: turn one against the others. But everyone’s lives are put at risk when one member of the team makes a surprising decision.

Risking it all, Alex works with Owen to infiltrate the Collaborators. When they begin to test her loyalty, Alex realizes she’s become a pawn in their plan to take down both the President and the task force.