For roughly its first half hour, "Waist Deep" looks as if it's going to amount to something solid among so-called "urban thrillers." Much like its hero, an ex-con-turned-single dad-security-guard named O-2 (Tyrese Gibson), the movie shows an unsteady, yet earnest resolve to fulfill modest expectations. And then, everything flies off the rails.
Hope for the movie holds out just a little bit longer than for O-2 -- or "O" for short. He's so into being the dutiful dad rushing to pick up his son (H. Hunter Hall) from school that he forgets to leave behind his sidearm at work. How it happens that a recently paroled man is entrusted by any institution to carry a gun is the first of many absurdities that aren't easily explained away.
Junior (the son's name) is napping in O-2's back seat when hoodlums seize both convertible and child. O takes down some of the thugs in a firefight, but the car is gone. The only lead O can grab comes from a comely hustler (Meagan Good), who becomes his reluctant partner. It turns out that Junior is being held for ransom by the Dirty Rat Who Sent Our Hero Up the River. Given the prosaic name of Meat (rap star the Game), the monster-mobster's venality is established by his willingness to sever limbs of those who make him mad.