Ben Affleck knows Boston. Ben Affleck knows Oscars. About a decade ago he won one for “Good Will Hunting” his Boston-based story.  In “Gone Baby Gone” he goes back to his hometown to this time write/direct a story about two detectives (real life brother Casey Affleck and Michelle Monaghan) who investigate the disappearance of a missing four year old girl.  Ben Affleck should never get in front of a camera again. He’s an instantly stunning and master director pulling gritty performances out of his actors.  Captain Doyle (Morgan Freeman) is overseeing the police unit and he knows the pain of losing a child.  His died a few years ago.  The mother (Amy Ryan) of the missing girl gives an Oscar worthy performance as a grieving mother with some trashy tricks up her sleeve.  Enter Detective Remy (Ed Harris) who believes in justice, determined to see all the world’s pedophiles put away. Yet the twist of this movie isn’t what it is, it’s what it seems. The plot slowly thickens and becomes one of personal vs. professional conflict to the bitter end. Which by the way, is not the cookie-cutter Hollywood ending you’d hope for.  Three and a half tiaras