The secret to some of the best HBO series is dirt. Not filthy language, not nudity--actual dirt. The muck in the streets of Deadwood, Tony Soprano's soldiers exhuming an incriminating body, the Fisher family tossing shovelfuls in the grave as Six Feet Under buried its lead character Nate--all this soil embodies the network's insistence on deprettifying its subjects.
So when HBO set out to make a drama about Rome in the time of Julius Caesar, Job One was to dirty up the Eternal City. Rome (Sundays, 9 p.m. E.T., debuts Aug. 28) eschews the popular white-marble myth. "Part of the brief...