Threshold

A mysterious alien object attacks a Naval ship and crew. Dr. Molly Anne Caffrey, a government contingency analyst, is contacted by the Deputy National Security Advisor, J.T. Baylock, to investigate the incident along with a special scientific team of her choice.

Gunneson reappears in Caffrey's house. Meanwhile, Lucas, Nigel and Ramsey try to break down how the alien signals and DNA operate and come up with some interesting theories. Cavennaugh's team tries to locate Gunneson other shipmates.

When a man at a fast-food restaurant is found with his head imploded, Molly and her Red Team investigate and begin to suspect the involvement of a group of military cadets, and the discovery that the infection has spread beyond the original Big Horn crew.

A patient at an psychiatric hospital in Ohio escapes and Molly believes he may have been infected by the alien signal after paintings of glass trees are found in his cell. After further investigation, it is suspected one of the missing Big Horn crew might be involved.

After a shipyard gang bust, a suspected fugitive Big Horn crewmember kills a police detective. Molly and Cavennaugh go undercover as Homeland Security agents. Unbeknownst to them, the real Homeland Security department is on the case.

As the signal from the Big Horn invades a Miami rave, the team investigates who have been infected, trying to prevent the signal from spreading to the population.