Restaurant owner Lorenz Adlon plans to build a large and modern hotel in the heart of Berlin at the Brandenburg Gate. He has the support of Kaiser Wilhelm II who often booked the hotel, after its opening in 1907, for state guests. Lorenz Adlon's friends and financiers include successful colonial entrepreneur, Gustaf Schadt. Alma, daughter of Gustaf and Ottilie Schadt, becomes involved with Frederick Loewe, son of the driver. To avoid a scandal, Ottilie Schadt claims the secretly born daughter Sonja as her own child. Gustaf and Ottilie arrange for Alma to marry the noble officer Siegfried Geschirr, but she refuses and turns to the American photographer Undine Adams, with whom she eventually emigrates to the United States where she remains until after the First World War. Her daughter Sonja stays with her grandparents and is raised as their daughter. The child's father, Frederick Loewe, gets a job as a Page in the Hotel Adlon, where he rises to the position of Concierge. The first part ends with the First World War and the revolution in Berlin, which eventually leads to the end of the Empire. After the loss of German colonies Gustaf Schadt returns to a fading Berlin and dies shortly thereafter. On his deathbed he shares with Sonja that in truth her supposed sister Alma is her mother. Alma returns to Berlin with her partner Undine for her father's funeral. She also contacts Frederick Loewe and is finally brought together with her daughter. Accompanying Alma and Undine is a German American, Hedda Berger, whose appearance in the Adlon arouses the interest of Louis Adlon.

Deeply struck by her husband's death Ottilie Schadt takes her own life. Alma returns with Undine to America but Sonja refuses to go with them and takes an apartment at the Adlon. There she meets the Jewish pianist and journalist Julian Zimmermann and falls in love with him. Against the will of his father Lorenz, Louis Adlon divorces his wife Tilly, with whom he has five children, in order to marry Hedda Berger. In 1921 Lorenz Adlon is run over by a truck at the Brandenburg Gate and dies shortly thereafter. Louis takes over the running of the hotel with his new wife and gets it through the turmoil of the inflation period. During the "Golden Twenties" the hotel blossomed, achieved world fame and was home to the most important personalities of the time. Sonja begins a career in broadcasting. She loses sight of Julian Zimmermann until she is invited some time later to his Jewish wedding to actress Tamara Lieberkoff. A childhood friend, Sebastian Antennen, brother of Siegfried Geschirr, accompanies her to the wedding. Siegfried is a member of the Nazi Party Sturmabteilung (SA – what is now know as the Brownshirts) and is a leading-man in Berlin. After an appearance in 1926 by Josephine Baker in Berlin, there are racist protests by an SA troupe under the leadership of Siegfried and there is a fatal shooting. A protest at the Berlin Police remains inconclusive. The 1930s, see Julian Zimmermann, who has separated from his wife, and Sonja Schadt together permanently. After the National Socialist seizure of power Sonja finds her broadcasting work more and more in conflict with the new rulers. Sebastian, meanwhile, is now in a leading position Broadcasting House. After the Reichstag fire Julian is arrested and sentenced to three years in protective custody.

Sonja visits Julian in protective custody and informs him that she is pregnant. Three years later, he is released and returns to Sonja and their daughter Anna-Maria. He wants to leave Germany. In his efforts to escape Germany Julian accepts a false British passport but the Gestapo find out and arrest him. Sebastian swears to Sonja hat he will spare no effort to ensure that Julian does not come to court, but is only deported abroad. Because he believes Sonja had betrayed him and opted for collaboration with the Nazis, Julian has disappeared with their daughter and is still missing. Sonja resists Sebastian's overtures and resigns from broadcasting. She finds a job at the Adlon on the front desk. At Hotel Adlon Louis has tried to keep out of politics, with the result that the Adlon is shunned by the Nazis, even though Louis and Hedda have joined the Party. During World War II, specially the Battle for Berlin, the Adlon is increasingly becoming a military hospital. 1945 - Louis and Hedda leave the hotel to see her estate in Fahrland. Frederick Loewe and his daughter Sonja hold the fort at the hotel. The ailing Louis Adlon is arrested and interrogated by a Russian commando. He is released, but dies on his way home to his estate of a heart attack. After the Battle for Berlin, Russians forces occupy the Hotel Adlon, which is still largely intact. There a wounded Siegfried, now an SS -Hauptsturmführer, has also found refuge and is hiding in the cellar. During a sweep by Russian soldiers a shooting causes a fire to break out, in which the hotel is mostly burned to the ground. Siegfried could not be found when Frederick Loewe tried to save him from the flames. The hotel is expropriated by the Russian occupiers and Sonja Schadt is entrusted with the supervisory commission. Sebastian, who lost a leg in the war, returns to Berlin. He is Sonya's partner and her partner in the management of the hotel. In 1952, an Israeli socialist at a congress in the German Democra