President Nelson has been found dead in the White House residence, and Vice President Nick Cappuano must take the oath of office. Nick's wife Sam, a homicide detective, knows that no first lady has held a job outside the White House, but she's determined to be the first. An unexpected issue with a diplomatic trip to Iran thrusts Nick into his new responsibilities, while Sam confronts a murder investigation that may have ties to a cold case from fifteen years ago. As everything around them spins out of control, Sam and Nick rely on their bond to see them through.