Oslo sends two new officers to attempt to make some sense of the anarchy in Fortitude. Dan Anderssen continues his descent into madness, bringing him face to face with a grief-stricken Michael Lennox.

A survivor of the deadly parasite makes a connection with Michael, but things take a violent turn. Dan continues to lose his grip on reality.

Michael hunts for the place he was held captive, and makes a shocking discovery. Annie Burgess arrives in Fortitude looking for answers.

Michael sacrifices everything for a possible future with Elsa. As his violent deeds catch up with him, Dan realises he will never leave Fortitude.