The enigmatic Dr. Helen Magnus recruits insightful forensic psychiatrist Will Zimmerman to join her in the quest to track, study and protect the strange and often terrifying creatures that secretly populate our world.

As Will attempts to help Alexi cope with his abnormality, Helen gets a visitor from her past.

Dr. Helen Magnus, her daughter Ashley, and new to the Sanctuary, Dr. Will Zimmerman release three women from a mysterious crypt in Scotland, bringing them back to the Sanctuary for refuge. Unbeknown to the team, and the women themselves, they have extraordinary powers. And their disappearance does not go undetected by a powerful cabal, resolute on reclaiming what it determines is theirs.