An urban quarantine happens in Atlanta following a deadly outbreak of a mysterious disease.

Lex finds out that a woman who had close contact with an infected patient has disappeared.

Controversial videos featuring chaos inside the cordon sees Lex requesting reinforcements.

Things become more dire inside the situation room. Lex becomes more frustrated by the false hope he's forced to send to the public.

Lex and Dr. Lommers clash over how to pull off a food drop within the cordon. Katie looks for answers.

Lex ends up clashing with Capt. Scott. The data recovery center is under attack.

Dr. Cannerts makes a major breakthrough that brings him one step closer to finding a cure for the virus. Meanwhile, after monitoring hospital surveillance from the day of the outbreak, Katie and Jake unravel the truth behind Patient Zero. Elsewhere, Jana and Suzy move forward with a plan to escape the cordon using the city’s underground tunnel system. Finally, a risky operation to extract the potential antidote from the cordon takes an unexpected turn.

As tensions reach a fever pitch inside the cordon, mobs of angry protestors take to the streets in an attempt to break free. Meanwhile, stuck in isolation and cut off from their chain of command, Lex and Dr. Lommers have no choice but to stand by helplessly as the cordon erupts into mass chaos. At the hospital, Jake attempts to lighten the mood by taking Katie on a date, but their happiness is short-lived after they discover that several of Katie’s students have gone missing. Meanwhile, with Lex nowhere to be found, Leo moves forward with their investigation, inching one step closer to uncovering the person responsible for the outbreak.

When Teresa goes into labor, Jana, Suzy and Sam band together to turn Bitscan into a makeshift delivery room. Meanwhile, after spending some time with Dr. Lommers, Lex grows concerned after noticing a sudden shift in her behavior. Elsewhere, Leo continues to unravel the conspiracy behind the virus outbreak, while Jake stumbles upon some damning information about who may be involved. Finally, fed up with his lies, Katie confronts Dr. Cannerts.

Lex and Leo clash over their next move after a failed plan threatens to unravel their entire case. When word begins to spread that there may be a way out of the cordon, Jana considers her options. Finally, an unexpected turn of events brings Jake and Katie closer than ever.

As Jana, Sam and Suzy pull together the funds they need to plot their escape, Jake considers his own options for breaking out of the cordon. Lex receives cryptic clues from Leo that lead him to an abandoned warehouse outside the city. Elsewhere, a widespread rumor leaves Dr. Cannerts’ life in danger. Finally, after seeking shelter at her grandma’s house, Teresa makes a difficult decision about her family’s future.

With only one shot to take Dr. Lommers down for good, Lex carefully plans his next steps. Jana, Suzy, Teresa and Xander make their dangerous escape out of the cordon, but unexpected road blocks threaten to destroy their chance of making it home. Inside the cordon, Dr. Cannerts and Jake make a breakthrough discovery following a risky experimental treatment. Finally, with time running out, Lex is forced to make a decision that will change his life forever.