My sentiments exactly, an amazing show from the creators of the Wire, a show which apparently everyone in the world has seen apart from me.
Based on the book by David Simon (creator of the Wire), Homicide: A Year On The Killing Streets, which chronicled Simon's year shadowing the Homicide detectives of Baltimore City Police, this show is gritty and procedural but a far cry from glossy, thrills-packed cop shows like Without a Trace (which I also love).
The detectives wrestle; not only with their many cases, but their relationships with each other, the superiors in the department and, sometimes, their faith. The show is really about how a person deals with a job that exposes them to the worst side of people, where their belief in goodness is constantly tested and our mortality is always at the forefront of their mind.
Some of the detectives are cynical, some idealistic, some religious, some superstitious. They are all explored and exposed, with none of them appearing to be heroes or villains; they're just people doing their job.
It is also a shock after watching a show like Without A Trace to see balding, overweight, badly-dressed and, frequently, very sweaty cops. You need to tune into the first few series to see this, however, as the TV Network put a stop to all this ugly crime-solving half-way though the show's life.