Jackson and Abraham travel to Robert's isolated lab to recover his research. Meanwhile, Jamie convinces Mitch to go to New Orleans with her to approach a sympathetic senator, and Gaspald convinces Chloe to join forces with him.

The team heads to Paris to investigate a group of bears whose trackers have gone offline. Mitch makes a shocking new discovery about the Mother Cell. Chloe runs into her ex-fiancé.

The team discovers a terrifying rat infestation when a cargo ship carrying the bloodthirsty rodents washes up off the coast of Massachusetts. Also, unbeknownst to the rest of the team, Mitch reconnects with his terminally ill daughter in Boston as he prepares to make a trade with Reiden-Global to save her life.

Jamie contacts a fellow journalist in an attempt to expose the truth about Reiden’s involvement in the global animal problem. After realizing Delavenne works for Reiden, Mitch escapes with both the Mother Cell and his daughter’s medication. However, on their way to deliver the medication, Mitch and Abraham come face-to-face with a terrifying army of birds.

Chloe is taken hostage by someone she knows. Jackson and the others are arrive at Zambia to find the leopard to test Mitch's theory of the animal mutation.

Chloe tries to bring light to the rising threat from the animals. Jackson is taken to a hospital and while they are there Mitch works to create a cure. However, there are many obstacles they must overcome.