The love affair between Andrea, laborer from the italian northern area called Bassa Lombarda and apulian single mother, Rosaria, is grafted on the background of the inconveniences of poor commuters who must go to work in Milan by train.

Caterina finds out that her husband Peter Tzar of Russia, is plotting to kill her. She sets Count Orlov free from prison, Peter's sworn enemy, becomes empress of Russia and leads the Cossacks army against him.