As people across the globe are experiencing hallucinations, MI5 agent Zoe contacts Bill for answers. Meanwhile Catherine Durand detects unusual black hole activity.

As Adina starts the next stage of her plan, astronauts Juliet and Richard see warning signs in space. On earth, they begin to uncover Adina's sinister mission.

With Richard's help, Catherine discovers she can travel to another world. Meanwhile, a new revelation puts Martha's loyalties to the test, and Zoe breaks Bill out of prison.

Tom grapples with a betrayal and encounters a familiar face. Catherine looks for a solution to the dangers of the black hole.

A deadly face off leads to a life threatening moment, whilst in the alternate reality, Catherine and Sam seek help for his parents.

Bill's latest discovery is put in jeopardy, even as trouble brews with the human aliens, and Catherine must decide where her loyalties lie.