Tobi and Ella's childhood in East Berlin in the 1970s is shrouded in mystery. Now adults living in London, their past is full of unanswered questions. Both remember their family's daring and terrifying attempt to escape, which ended in tragedy, but where did their parents disappear to, and why? What happened to Heiko, their little brother? And was there ever a painting of three blue horses? A powerful story of East and West Berlin.