S4, E4: With Freamon and Greggs moved to Homicide, Herc and Dozerman join Marimow in the stripped-down Major Crimes Unit. Cutty gets a 'custodial' job at Tilghman School mopping up truants, but can't make headway in his efforts to mentor Michael. Bubbles gives Sherrod an ultimatum in an effort to get him back in school as a 'socially promoted' eighth-grader. Burrell finds a way to sabotage the state-witness murder investigation before the election, a plan that directly impacts Greggs. Prez's struggles in class continue; Bodie finds himself working for a new 'company'; Colvin pitches his pilot program to the school; Carcetti meets with a constituency he knows won't support him; Randy faces a dilemma after being busted for his candy scam; Marlo is schooled in poker; Royce antes up in a game he can't lose; and Proposition Joe plays Marlo in a high-stakes heist.