Harry Van, an American World War I veteran, tries to re-enter show biz and ends up in a mind-reading performance with an alcoholic partner. There he meets the mysterious Irene, an acrobat, who claims to come from Russia and wants to become his performance partner. They have a romantic night but Harry decides to stay with his previous partner.
Twenty years later, after a number of jobs, Harry escorts a dancing group of six blondes on a trip through Europe. They get stranded in an alpine country, where they have to wait in a hotel until the border opens again: the international situation is close to war.
It is here that Harry meets Irene again, who is the mistress of a rich entrepreneur, Achille Weber. A pacifist told the people in the hotel that Weber is behind the war that just started, and that the planes the guests saw rushing away from a nearby air field are carrying bombs to kill thousands of people in other countries. The pacifist is imprisoned and it is later mentioned that he was killed.
The next day the people in the hotel are able to continue their voyage, as the borders have opened again. Also the American society manager is leaving, telling Harry and his blondes that the other countries will take revenge and bomb the hotel. But Irene cannot leave the hotel because she "told the truth she had always wanted to tell" to Weber - imagining the deaths of the young couple they had met in the hotel due to the weapons that Weber manufactures. To exact revenge, Weber refuses to vouch for Irene's "League of Nations passport". Irene has no valid passport and cannot travel on her own, so she must stay in the country.
Harry, who had already left with the blondes, reluctantly comes back for Irene. She then admits that she is the person he had met in America twenty years ago. Harry says that he wants to take her with him and the blondes. They hear planes approaching and are told that they should seek shelter in the cellar..