At the end of Season Five, Fiona turned herself in to the authorities for the bombing of a British Consulate to eliminate any leverage Anson Fullerton had over her and Michael. Anson tried to force Michael to rebuild the organization that burnt him, but with Fiona behind bars, Anson lost all his leverage.
Season Six begins with Anson on the run and Michael reeling from the loss of Fiona. If he doesn't want her sacrifice to have been in vain, Michael will have to stop Anson before he can disappear forever. Desperate to escape, Anson sends an assassin to Madeline's house and leaves a trail of bodies in his wake.
Despite all the obstacles Anson throws in his way, Michael manages to corner him into a coastal industrial plant. But for Michael, the price for catching Anson may be higher than he's willing to pay.