The novel follows the Berry family, whose eccentricities and resilience are tested over generations, particularly through their experiences running various incarnations of the eponymous hotel. From their original establishment in New England to a second in Vienna, the Berrys encounter a cast of quirky characters, endure tragedies, and navigate complex relationships. Themes of love, loss, and the pursuit of dreams are explored against a backdrop of political and social upheaval, with the family's unique motto, "Keep passing the open windows," serving as a refrain for their determination to persevere in the face of life's absurdities and challenges.

The novel is a thrilling tale of Nazi hunters discovering a sinister plot by Josef Mengele, the infamous Auschwitz doctor, who is orchestrating a series of assassinations across the globe. The hunters uncover a chilling plan to clone Adolf Hitler and raise the resulting boys in environments similar to Hitler's own upbringing, in an attempt to recreate the Third Reich. As the protagonists race against time to thwart Mengele's plans, they face moral dilemmas and the terrifying prospect of history repeating itself through these young clones.