When she was young, a skiing accident caused Alice (Alba Lowatcher Alba Rohrwacher) to break her leg, and the pain will accompany and change her life forever. Genius Matia (Luca Marinelli Luca Marinelli) hides a very dark secret under his friendly and pure appearance. His mentally retarded twin sister did not bring him a sense of pity or responsibility. on the contrary, he wanted to get rid of this annoying burden forever and ever, and one day he did. Childhood trauma to children is sometimes more than expected blow, Alice and Matia these two ordinary and special people, they grow up with trauma, mature. They are like prime numbers in a series, cold, lonely, hard, eager for the appearance and proximity of the same kind, but unable to help themselves to hurt each other. They met, fell in love, tortured each other and then separated to find their partners, but it was destined that they could not be separated. In this autumn, whether these two prime men and women can save each other, or whether they are waiting for them, is to go to the silence hidden in the dark.