With Ashley and Henry in the hands of the Cabal the rest of the team venture to a remote vampire enclave to recover the last known sample of vampire blood; the power they need to defeat the Cabal.
SCIU has surrounded the 5th Ward with troops and an electric shield that prevents them from leaving. Caleb has a virus that can turn the human population into abnormals. Magnus enacts her ultimate plan for the Sanctuary network.
The expedition to Hollow Earth is on, as the team searches for a way to cure Dr. Magnus. But instead of salvation, they may find something more sinister waiting below. Special appearance by Polly Walker from Caprica.
In an unprecedented alliance Druitt and Sherlock Holmes work with Sanctuary to deduce why normally placid abnormals are running amok. Their plan, infiltrate their prime suspect, The Cabal.
The Cabal's new "Super-Abnormals" begin destroying Sanctuaries around the world. It won't be long before they launch their attack on the Old City Sanctuary, and Magnus must choose between saving Ashley and saving the Sanctuary Network.
After peaceful Abnormals worldwide act up at the same moment, the incident is linked to an EM pulse originating in Mumbai. Will and Kate go to investigate, and they soon discover that the event may relate to a dangerously-powerful Abnormal.
Big Bertha is not happy, but Dr. Magnus has a suggestion for how Will might once again be able to contact her, through her Kali avatar. Third and final installment of the Kali trilogy.
When a deadly Abnormal hatches prematurely inside a bank vault and escapes, Kate, Will, and Helen must stage a hold-up to buy themselves time to search for the Abnormal before somebody dies.