John Matthews has made a good life for himself having worked hard to build up his construction company and made many a contact along the way. So when John's estranged son stupidly takes in a delivery of drugs for a mate and ends up facing a mandatory 10 years he will do what ever he can to help even when his son refuses to snitch on others. So after calling in some favours to meet with DA Joanne Keeghan (Susan Sarandon) John volunteers to go undercover to help the DA and DEA arrest the bigger dealers, bribing one of the ex cons who works for him to introduce him to the right people. But the choices John now makes have huge consequences forcing him to use all his skills and courage to survive.
So a dad will do anything to save their child. It is such a familiar theme that it would take something really special to make any movie using it to be anything more than average. The bad news is that "Snitch" is nothing special and at times is quite an arduous slog as director Ric Roman Waugh tries to be different by not rushing to the excitement. I suppose if "Snitch" had starred someone such as Ralph Fiennes or Kevin Bacon in the father role that might have worked but when you have action man Dwayne Johnson in the lead role keeping things slow is not giving the audience what they expect and in most cases want.
But having said that I am not sure a change in lead actor would have made "Snitch" any better because it is only a variation on that old storyline of a dad willing to risk his own life to save a child's. As such drug dealers, chase scenes, reluctant partners in crime as well as secrets and lies "Snitch" has it all and if it was the first movie you ever watched featuring a father trying to save a son you might be impressed but it is a huge might because there is nothing here which isn't familiar.
What this all boils down to is that "Snitch" is technically not a bad movie, it hits all the points it is aiming for be it the characters or the action. But it is such a slow moving movie that those who watch expecting big action from Dwayne Johnson are likely going to struggle to keep interested in it.