Norwegian Crown Princess Martha (Sofia Helin) and her husband Prince Olav visit U.S. President Franklin Roosevelt (Kyle MacLachlan) in 1939. A year later they must flee the Nazi invasion of their country.

Prince Olav and the King plan their escape. Meanwhile, Princess Martha and the children take refuge with her Swedish royal relatives. But the Nazis threaten the King if he harbors the Crown Princess.

While bombs fall on Olav and the King in London, Martha and the children are in the U.S. where President Roosevelt extends a special invitation.

Martha is pressured to exploit her friendship with the president. Roosevelt defies isolationists to push the Lend-Lease act. Martha and the children get a surprise Christmas present.

Martha uses dinner-table tactics to help Norway. The first lady gives Martha unusual lessons in public speaking. The president gets on dangerous ground with Martha.

America enters the war, and Olav arrives from England. Missy grows suspicious of ties between Roosevelt and Martha, as does Olav. Meanwhile, a dastardly Nazi plot unfolds.

A Nazi agent slips through the cracks, putting the children at risk. Martha travels to England and gets a shock. A Norwegian war hero meets a tragic fate.

With the war almost over, Roosevelt’s health takes a bad turn. Olav tries to keep Norway out of the clutches of the Soviets. He also faces rocky relations with Martha.