The assassination of a seemingly ordinary Brooklyn plumber launches the team into a globe-spanning investigation that ruffles feathers with the CIA.

The team is on the case when a suburban couple is murdered and all forensic evidence points to the home's previous owner, who is currently serving 10 years in federal prison.

After a series of targeted bombings in Queens, the team fears a citywide gang war is imminent – until a tip from OA's old Army buddy, Clay, directs their attention to an unexpected and powerful foe. Meanwhile, Scola continues to struggle to find a new partner.

When the sister of Sydney Ortiz is the victim of an attempted kidnapping and sexual assault, Sydney seeks help from Isobel and the team in tracking down a meticulous serial offender who leaves no evidence behind.

When a chaotic campus protest turns deadly, the team is called in to help quell the mayhem and track down the murderer. Meanwhile, Jubal is concerned when Tyler is detained along with a group of student protestors.

The team is called in to track down a serial killer after the bodies of multiple women with the same physical description are found scattered across the city. Meanwhile, Maggie juggles her roles as a guardian to Ella and an FBI agent.

After a park ranger is shot dead by a masked assailant on Governors Island, the team discovers a string of connected crimes that leads them to their toughest roadblock yet: an online conspiracy theory community.

After three customs officers are shot dead in a cargo heist, the team entrusts OA's old army buddy Clay to help determine if it was an inside job.

The investigation into an assistant U.S. attorney’s death leads the team to a related airline whistleblower scandal and the chilling discovery that they don’t have much time to thwart terrorists from crashing numerous in-flight commercial airplanes. Dealing with the memory of his brother, who was a 9/11 victim, the case pushes Scola hard to prevent another catastrophe.