Professor Rypar (Alois Švehlík) is an old, cantankerous university professor who lives alone in Prague. One day he finds a young Vietnamese man Song (Duy Anh Tran) – an immigrant in search of a better future - on his roof, and decides to take him in. The co-existence of a hostile master, angry at the world that eludes him, and a young man looking for a way out of a desperate situation in an unfamiliar city creates many tragi-comic situations, throwing up surprising ideas and solutions. But can you trust a stranger and can two culturally different people share the same space?