Season 4 begins Commander-in-Chief Frank Underwood (Kevin Spacey) fighting for his political life with principled insurgent Heather Dunbar (Elizabeth Marvel) threatening to wrest the Democratic Party presidential nomination from him.
Yet the biggest menace to his Presidency is posed by someone closer, First Lady Claire Underwood (Robin Wright) who has disappeared since her bombshell announcement at the end of season 3.
But it soon becomes apparent that Claire is merely the start of his difficulties as unhappy ghosts of his past re-emerge to haunt him.