USSR, 1942… Trains, an endless stream of injured soldiers speed into the rear, tireless doctors operate non-stop, and still, so many fighters do not survive. But one day, a strange woman appears on a military sanitary train going to Kirov. She keeps her past a secret, but her medical skills blow the minds of the experienced surgeons. Who is this fragile woman? Where is she going, and where did she come from? And what is she carrying in her large suitcase?