It's been ten weeks since his wife, Alex, was killed in a car accident; and President Kirkman's senior staff insist he seek professional help in dealing with his loss, forcing him to reluctantly see therapist Dr. Adam Louden. Meanwhile, FBI Agent Hannah Wells and Aaron Shore travel to Cuba as part of a trade delegation, but the trip does not go according to plan. With lives in the balance, Kirkman is challenged with a decision that will test his role as commander in chief during this time of personal tragedy.
On the night of the State of the Union, an explosion claims the lives of the President and all members of the Cabinet except for Secretary of Housing and Urban Development Tom Kirkman, who had been named the Designated Survivor. Kirkman is immediately sworn in as President, unaware that the attack is only the beginning of what is to come.