In early '90s Boston, Jackie Rohr, a renowned FBI agent, does not mind the culture of corruption or quid-pro-quo politics. But Decourcy Ward, the ambitious new Assistant District Attorney, wants to uproot the system. When an armoured truck heist in Revere leaves three guards missing, Jackie and Decourcy struggle to align their moral compasses. However, the two men find themselves in a faux-alliance that may, ultimately, turn into something real.

After an eventful Sunday at church, Decourcy finds out he has a powerful new enemy in town.

Jackie searches for his absent informant as Jenny searches for purpose, revisiting her passion to become a teacher. Decourcy works up a plan to overcome the town's infamous "Code of Silence" and get a few suspects to talk. Minogue is assigned a big case, but not the one he actually cares about. Jimmy skips town to visit his kids and finds that, even a thousand miles away, he's not safe from his problems back home.

Jackie strong-arms Jimmy to get a step closer to finding the presumably dead armoured truck guards. Decourcy rattles a suspect called to testify before the Grand Jury.

Jackie and Decourcy continue to hunt down the weapon connected to the Revere robbery; a local reporter gets a tip about a story that could lead her down a treacherous path.

Decourcy is a step closer to connecting the stolen guns to the Revere robbery when an insider agrees to talk. Jenny is no longer able to ignore Jackie's indiscretions after they show up on her doorstep.