Robert De Niro is particularly wonderful as a kind priest that tries to teach these boys morals and fundamental wisdom for living life. De Niro plays it very empathetic and subtle in his acting. De Niro's priest functions as their collective father figure and a source of guidance. It's one of Robert De Niro's most understated roles. He is so good.
Kevin Bacon is another notable role in Sleepers. He is the most vile and reprehensible villain in Sleepers. He eats up the scenery when he is one screen in Sleepers. His heinous actions are hidden away behind his calm and collected demeanor. Bacon delivers one of his finest performances in his career. It's like a crash course in cruelty. Bacon is brilliant!
Check out Sleepers if you dare.
A decent first act isn't followed up with a suitably engaging last act even with the best cast possible at their disposal.