The Solitude of Prime Numbers
[2] The title is explained by arguing that protagonists Mattia and Alice are like twin primes: both lonely, close to each other but separated by an even number.Mattia and Alice (children in 1984, teenagers in 1991) are both traumatized, and isolate themselves from the people around them.When he was a child, Mattia's mentally disabled twin sister Michela went missing whilst he was supposed to look after her.When Alice was a child she had a skiing accident; which results in her having a permanent limp and a significant scar on her thigh.They meet while teenagers and become friends, but lose contact when Mattia goes to work in Germany.