Four boys from West Baltimore, Michael, Namond, Randy and Dukie, play out their summer vacation in the streets. The boys are then stirred into action when Dukie is beaten up, leaving Randy to concoct a retaliation plan against the rival gang.

Herc's soft-duty job with the mayor takes an unexpectedly hard turn. Meanwhile, despite the potential damage to her career, Pearlman provides Freamon and Sydnor with subpoena ammunition for their 'grizzly bear' hunt in City Hall.

With his poll lead shrinking, Royce resorts to extreme measures to stall Carcetti's momentum. Meanwhile, Michael proves adept as a runner, alerting both Bodie and Marlo, and Rawls replaces Asher with 'company man' Charles Marimow, who pushes a new agenda on the detail.

With Freamon and Greggs moved to Homicide, Herc and Dozerman join Marimow in the stripped-down Major Crimes Unit. Meanwhile, Cutty gets a 'custodial' job at Tilghman School mopping up truants, but can't make any headway in his efforts to mentor Michael.

Valchek leaks details of the Braddock case to Carcetti, who contemplates how to best leak it to the press... with the ensuing negative attention turning Royce against Burrell. Meanwhile, at school, Prez's reward and punishment programme meets with mixed results.

With Election Day near, the three mayoral candidates make last-minute appeals, with Carcetti seeking votes as he responds to a potentially devastating smear. Elsewhere, whilst following through on a promising video lead, Herc finds out just how elusive Marlo can be.

With the election finally over, Royce and Carcetti make their peace and contemplate their respective futures. Meanwhile, Marlo looks to identify his pursuers, infuriating Herc, who begs Carver to help; and Omar, who has a bounty on his head, calls in a favour to Bunk.

To monitor the pulse on the street, Carcetti makes the rounds with members of the force. Elsewhere, Herc, who has Marimow on his case, decides to resort to strong-arm tactics to retrieve his stolen camera, but Marlo isn't impressed.

After being in prison, Poot returns to the corner and is welcomed back by Herc and Dozerman. Meanwhile, Carcetti engages in a battle with City Council President Campbell; rewards Daniels with a promotion; and hits a snag in his efforts to relieve Burrell of his duties.

Acting on Clay Davis' advice, Burrell seeks to burnish his reputation by ordering the department to double the number of street arrests. The mandate does not sit well with McNulty though, who instead sets his sights on cracking a string of church robberies.

After flexing his muscles around the city, Carcetti faces his first dilemma when a group of ministers protest Herc's mistreatment of one of their own. Meanwhile, Michael and the boys enact an elaborate revenge plot on a mean cop, and Namond takes a leap of faith.

On the trail of missing bodies, Freamon turns to a higher authority after being rebuked by Landsman. Elsewhere, Colvin approaches Deacon and Watkins to help keep his experimental class funded, and Bubbles considers taking extreme measures to rid himself of his nemesis.

The bodies from the vacants continue to pile up while Burrell offers his support to Daniels and forgives Rawls for crossing him. Elsewhere, Bubbles' revenge plan backfires, and Proposition Joe looks to the Co-op to pay shipment losses... but finds them uncooperative.