The third isn't the last season, but it feels like it could have been. The final ruin of the Barksdale crew finally closes the door on the investigation that started the series; most of the principles get closure, or something near enough to it.
David Simon's obsession with the debasing power of institutions is back in full force. City councilman Tommy Carcetti (Aidan Gillen), Commissioner Burrell (Frankie Faison) and Mayor Royce (Glynn Turman) add a political element; Stringer plays businessman with Clay Davis and crooked contractors while his and Proposition Joe's drug co-op ruins the game; an innovative crime-prevention strategy is bound, from the very start, for failure. And one lonely convict tries to recover after 14 years in prison.
There's too much to take in and far too much to write about: it's as good as it ever was, dense and compelling, with a painful failure to take the entertaining way out.
Season One
Doesn't hold up quite so well on a second viewing. Still superb, no longer genius.