Golden Horn, Bosporus, the ancient Byzantium: Angelika Overath tells the story of a city full of beauty and contradictions, where the past remains alive. Cla, a religious teacher from Engadin, wants to spend a winter in Istanbul. He is working on a study about the Constantinople mission of Nicholas of Cusa. But as soon as Cla meets the young Turkish waiter Baran, he dives into the city with him: they wander through the streets and markets, sit by the sea and in cafés, and go to the hamam. In their conversations, the late medieval world with its division into Eastern and Western churches collides directly with the religiously divided Istanbul of today. At a secret meeting of the dervishes, Cla experiences how close Christian mysticism and Islamic Sufism can be. Unintentionally, he has fallen in love with Baran. It is only when his fiancée from Switzerland comes to visit that he becomes aware of the magnitude of his feelings.