In chronicling a multi-generational family
business dealing illegal drugs and the efforts
of the Baltimore police to curb their trade, this series draws parallels between these organizations and the men and women on either side of the battle.

It starts as mid-level drug dealer, D'Angelo Barksdale beats a murder rap. After a conversation with a judge, Det. James McNulty has been assigned to lead a joint homicide and narcotics team, in order to bring down drug kingpin Avon Barksdale. Avon Barksdale, accompanied by his right-hand man Stringer Bell, enforcer Wee-Bey and many lieutenants (including his own nephew, D'Angelo Barksdale), has to deal with law enforcement, informants in his own camp, and competition with a local rival, Omar, who's been robbing Barksdale's dealers and reselling the drugs. The supervisor of the investigation, Lt. Cedric Daniels, has to deal with his own problems, such as a corrupt bureaucracy, some of his detectives beating suspects, hard-headed but determined Det. McNulty, and a blackmailing deputy. The show depicts the lives of every part of the drug "food chain", from junkies to dealers, and from cops to politicians.