A woman with information about the death of Maggie’s husband is abducted, leading OA and the team to uncover a criminal operation larger than anyone imagined. Also, Dana puts her career in jeopardy when she stands by and allows Maggie to work on this case that has such a personal connection to her.

When an officer is shot dead at a pawn shop along with the store’s owner, the team tries to figure out why a young, recent Ivy League dropout is tied to the crime.

The abduction of a young woman leads the team back to a cold case from 18 years ago, which pushes Isobel to reconnect with her old partner Jake and take another shot at solving one of her first cases in the bureau.

After a mysterious bioweapon leaves two MTA workers dead and one injured, the team rushes to determine who is behind the attack and the location of their next target; Jubal’s past demons begin to surface.

After Jubal narrowly escapes a calculated assault on a secret FBI office, the team discovers a rogue terrorist group has infiltrated the FBI. Unsure of who to trust, the team must work in the shadows to unmask the culprits threatening the sanctity of the New York field office.

An American diplomat is killed while being used as a pawn in a dangerous drug ring, and the team must work together to bring them down. Also, Jubal and OA try to help friends from their past fight off their inner demons.

When a controversial senior leader from Egypt comes to New York for a heart transplant, OA struggles to balance his personal opinion with his professional duty when he is assigned to the security detail.

After a decorated FBI agent is murdered, the team investigates and uncovers the man led a double life. Also, Maggie struggles with what information she should reveal to the agent’s widow, who is also her personal friend.

When the deputy commander of an Air National Guard Base is kidnapped and forced to give over access codes, the team must work quickly to find the suspect along with stolen ammunition. Also, Scola questions his own safety in the aftermath of a recent traumatic experience.

When a trucker is gunned down after a routine trip from Canada, all signs point the team to a noted criminal on the FBI’s Most Wanted Terrorists list. Also, Jubal gets to work with an old friend and colleague, Detective Jack Lombardo.

When an alt-right provocateur is murdered after giving a speech at a university in New York City, Maggie and OA investigate the school's more extreme political groups and rely on OA's sister, Amira, a student, for help.

The team pivots when their sting operation to secure a massive bomb from an illegal broker leads them to discover that the device is already in the wrong hands. Also, Jubal’s promise to be present at his son’s birthday party is put to the test as the case continues to heat up.

The team investigates a series of brutal assaults; OA hides information about his own mugging.

Maggie returns from medical leave in time to help the team investigate two homicides: a law student on track to attend the FBI Academy and a young man with possible gang ties. Also, an inadvertent revelation from Maggie causes OA to worry that she is rushing back into the job too quickly.

A teen shows up at FBI headquarters with a large bag of fentanyl, seeking the team's protection from the men who shot his father; Nina goes to Scola with a proposal he is hesitant to accept.

The team jumps into action when analyst Kelly Moran is taken hostage.

As the team investigates a deadly robbery that garnered a cache of automatic weapons for the killers, they discover one of the perps is a classmate of Jubal’s son, who is reluctant to cooperate with the case.

To aid Scola in his undercover mission to find the terrorists believed to be behind the imminent attack in New York City, Maggie calls in Remy, whose well-connected informant from a prior case may be key to moving the operation forward. The crossover starts on FBI: International S02E16 Imminent Threat (I). It continues on FBI: Most Wanted S04E16 Imminent Threat (III).

A drug dealer is shot in a federal park and the team sets out to look for his killer; Maggie's sister returns to New York and complicates the case.

After finding a group of teens dead from a drug overdose, the team races to find the dangerous dealer and his supplier. Meanwhile, OA questions where he stands in his faith.

When a prominent doctor is found dead in a ritualistic slaying, the team must race against time to hunt down a religiously motivated serial killer. Also, Scola faces a life-or-death decision.

When a passenger train is hijacked and rerouted while at high speed with an unarmed OA and Gemma on board, the team races to wrest control away from the unhinged perpetrators and prevent a catastrophe.

After a key witness and a U.S. marshal are ambushed and killed, Maggie and OA must track down a man who leaked the information that led to their murders.

When the daughter of a wealthy family is kidnapped in an attempt to gain notorious internet fame, Maggie and OA discover the kidnapper’s plans go far beyond abduction in order to never be forgotten.

After Rina is critically wounded while heading to work with Jubal, the team makes the chilling discovery that a vengeful Vargas orchestrated the shooting from behind bars and continues to target the rest of their team and their loved ones.