The investigation leads to a serial killer linked to Theo who, with Penny, seeks an unknown source to help them get away. Meanwhile, recent events send Ryan on a downward spiral, as a search to find the FBI agent accessing Daisy's laptop intensifies.
The latest unsettling discovery results in Ryan being stalked by the new killer, which leads to a game of cat-and-mouse that involves Joe Carroll. Meanwhile, Max and Mike search for the clue that was stolen, while Mark makes a decision that shocks all.
The FBI closes in on a suspect they believe responsible for the latest murders, but Ryan isn't sure they have the right person, which sends him digging deeper into more dangerous territory. Meanwhile, Joe is evaluated as his execution date nears and a new threat attempts to cover his tracks.
A tip leads Ryan and Mike to track their latest target to a small town, where they discover an even more dangerous threat who has been able to stay off the authorities' radar. Meanwhile, Max struggles to make a confession.
Ryan may have been able to connect Andrew to Mark, but he and the FBI are unsure of how things may tie into Joe Carroll. Meanwhile, tension mounts among Mark, Kyle and Daisy, and Ryan is placed in a serious situation.