Conclusion. Two ships are wrecked and a tidal wave races toward the coast of Mumbai, India, following Wexford's attempt to kill "Big Bertha." When Wexford tries to kill the creature again, Magnus risks her life to intervene in the Season 3 premiere.
Magnus and the team go to a bank to retrieve an Abnormal that was stashed in a safe deposit box, which not only hatched prematurely but also escaped, prompting Kate to enforce a less-than-subtle quarantine of the bank's customers.
Nikola Tesla sends a distress call to the team, and they track him to the Colombian highlands, where they encounter deadly multipedes. Meanwhile, Bigfoot and Kate learn that a long-time friend has been murdered in Old City.
A werewolf sighting brings Will and Henry to England, where they learn of suspicious happenings at a psychiatric facility. Meanwhile, Magnus and Tesla work together to probe the mysteries of the holographic city.
Magnus tells Will about her past with Adam Worth (Ian Tracey) and his link to "The Five"; Tesla divulges that Druitt may have additional information about Adam; Will makes a shocking find while analyzing blood tests.
Adam is released from his restraints so that he can help Will find an access point for the hidden city; Magnus and Druitt go to London to find a critical artifact, leaving Will to manage the Sanctuary.
The team goes to Tibet in search of the hidden city, which is rigged with deadly security measures; back at the Sanctuary, Adam admonishes Tesla and Druitt for letting Magnus go to the city without him.
For trespassing in Praxis, the team is sentenced to death, but Ranna needs Magnus to gain insights into Adam and the tremors that are affecting the city. Elsewhere, Druitt contends with cannibalistic creatures.
Magnus returns to a disheveled Sanctuary just hours before it is to be inspected by the chief of a UN security team. She first encounters a battered Henry, who claims he was attacked by Will, and learns that Bigfoot is missing.
A dinner date goes awry for Will and Abby when they are abducted at gunpoint on their way to a restaurant. Magnus puts a halt to the team's rescue operation upon determining the identity of their abductors, leaving Will and Abby's survival in their own hands.
Magnus and Tesla probe a Praxian stronghold and uncover secrets about the vampire race. Meanwhile, Kate shares a dark part of her past while tracking a drug operation that uses live amphibious Abnormals.
Season 3 finale: Abnormals from Hollow Earth emerge in large numbers from a cave in South Dakota, prompting Magnus to cooperate with the military; and Druitt resurfaces and warns Magnus of a plot he hatched with Adam Worth.