This public-school powerhouse in junior high chess competitions has won more than 30 national championships, the most of any school in the country. Its 85-member squad boasts so many strong players that the late Albert Einstein, a dedicated chess maven, would rank fourth if he were on the team. Most astoundingly, I.S. 318 is a Brooklyn school that serves mostly minority students from families living below the poverty line. Brooklyn Castle is the exhilarating story of five of the school's aspiring young players and how chess became the school's unlikely inspiration for academic success.