War threatens in Europe, but President Franklin Delano Roosevelt would rather enjoy the company of his guests and talk of pleasanter things, unlike his wife Eleanor. It’s a beautiful day in 1939 at his ancestral home in Hyde Park, and the Crown Prince and Princess of Norway are visiting. They’ve been touring the United States, and have stopped to meet the President. FDR and Princess Märtha take a liking to each other.
Less than a year later, thought of war can no longer be avoided. World War II has officially begun with the invasion of Poland by Germany. Norway is neutral, but Germany needs steel, so the Scandinavian country may not be safe for long.
Crown Prince Olav is having blackout curtains installed at Skaugum, the royal residence outside Oslo where he, Märtha, and their three children are living. Märtha is trying to shield the children from fear, preventing King Haakon and Olav from discussing the war in front of them.
But the war is growing ever closer. German planes have attacked a Norwegian passenger ship in the North Sea, and several Norwegian merchant ships have been sunk by the Germans. Olav fears a German attack on Norway itself, and is upset that the Cabinet and Parliament are doing nothing.
At a reception, he and his father Haakon accost the prime minister, urging action against the Germans. But the prime minister simply says that the Germans aren’t the only ones prowling the North Sea; so are the British. Neither side warrants risking Norway’s neutrality.
Desperate for information, Märtha corners Florence Harriman, the United States’ representative in Norway. Is Germany planning to invade Norway? Does the U.S. have any pertinent intelligence? Harriman is evasive in her answers but mentions the importance of steel and ends the conversation with a terse comment: “Prepare for the worst.”
Early morning, April 9: German forces are massing; an invasion of neutral Denmark and Norway seems imminent. Märtha fearfully packs a bag to take to a remote cabin with the children, while Olav will take up a role in the military after escorting his family to safety. An air raid horn blares.
Ragni and Nikolai, attendants of Olav and Märtha, quickly prepare to evacuate with the royal family. Their two older children, Rolf and Ulla, are away at a Red Cross preparedness exercise, so Nikolai leaves a note and money for them to take the bus to Hamar, where they can meet him, Ragni, and their youngest son Einar.
Everyone meets at the train station: the royal family, their attendants, the Cabinet, the Parliament. Germany has already taken several Norwegian cities overnight. Norway has sent out a mobilization order, but Olav is furious that it will be too late and too slow. He and Märtha ride in a separate train car from their children, lest the train is bombed and they are all taken out in one swoop.
Not far outside Oslo, German planes fly over the train, which suddenly pulls to a stop at a station. Everyone evacuates the train to shelter in a tunnel below the station as bombs fall. The government and royal family continue to flee by car after the bombing stops.
German soldiers take the royal residence of Skaugum. Denmark has already fallen.
Ragni worries that Rolf and Ulla will not be able to find her and Nikolai, as they may not end up in Hamar after all. The children will probably not be able to leave Oslo, Nikolai says; the roads are blocked. He and Ragni have their duty to the royal family. The government caravan continues on to Elverum.
Märtha wants to cross the border to safety in her native Sweden but Olav and Haakon do not want to abandon their country. So she sets off with the children towards Sweden, with Nikolai driving and Ragni and Einar accompanying.
On a lonely road surrounded by snowy forest, the car gets a flat tire. As Nikolai changes it, he hears rustling in the dark woods. Märtha tells her kids that they’re playing hide-and-seek, and should crouch in the back seat so Nikolai can’t see them. Men emerge from the trees: Swedish soldiers on skis. They salute Märtha and let the car go on its way.
The guards at the border are less kind, refusing to let the family pass without passports, despite Märtha’s identity. She makes a bold decision and tells Nikolai to drive through the barrier. No one stops them.
Nikolai deposits everyone at a Swedish hotel, then returns across the border to try to find and help Olav, leaving Ragni and Einar with Märtha and her children.
Olav, Haakon, and the government have been sheltering in a remote location. When German planes fly over and begin dropping bombs, they flee into the woods. In the chaos, Olav loses sight of his father.