Gone Baby Gone centers on the disappearance of a young girl in the working class neighbourhood of Dorchester in South Boston. The girl's aunt Beatrice McCready hires two private detectives Patrick Kenzie and Angie Gennaro. The detectives freely admit that they have little experience with this type of case, but the family wants them for two reasons – they're not cops and they know the tough neighbourhood in which they all live. As the case progresses, Kenzie and Gennaro face drug dealers, gangs and paedophiles. When they finally solve the case, they are faced with a moral dilemma that tears them apart.

Ben Affleck reinforces his creative talents as director.

Five years ago, Ben Affleck’s brilliant career came to screeching halt when he made Gigli with his then-girlfriend Jennifer Lopez. Since then he’s tried mightily to stage a comeback as an actor, all to little avail. But now B-fleck appears to have found his calling, and it’s behind the camera. He’s done a superb job as director and co-writer of Gone Baby Gone – the adaptation of crime writer Dennis Lehane’s novel of the same name. Lehane also wrote the source novel for Clint Eastwood’s Mystic River but this film is even better than that acclaimed movie.

Ben’s little brother Casey Affleck plays Boston Private Investigator Patrick Kenzie. He and his gumshoe girlfriend Angie, have been roped into the search for an abducted girl. Patrick’s strength is that he knows the various low-life elements of the city. His questioning quickly reveals that the girl’s mother is a cokehead whose criminal connections might have led to her daughter being abducted. But that’s just scratching the surface of a dark, twisted and tragic set of circumstances.

Casey Affleck hasn’t been an actor I’ve rated till now – he is a revelation as the determined, tough and ultimately moral hero. Michelle Monaghan brings a sad, soulful touch to the reluctant Angie, there’s sterling work from Morgan Freeman as a veteran police office, and Ed Harris delivers an electrifying, career-best performance as a hard-nosed detective.

The script is filled with mordantly amusing dialogue and riveting plot twists and Affleck makes the seedy side of Boston live and breathe every bit as well as Scorsese did in The Departed.

What’s extremely impressive is how Gone Baby Gone engages with ideas of vigilante justice in a thoughtful way without trumpeting the theme. It’s hard-edged and touches a nerve and a must-see for fans of smartly layered crime thrillers.

As a movie you shouldn’t let pass you by, Gone Baby Gone rates four and a half stars.