I have watched the first series and I found it very refreshing for a US Cop Drama.
For a start, the Wire does not patronise the audience, by presenting a main case per episode, with a few side cases, and it's all nicely wrapped up at the end and the cops go home for tea, cake and medals.
The Wire assumes the audience are intelligent, observant, and want more than a 45 min, all loose ends wrapped up fix.
The Wire demands your attention, and if you don't focus on the storyline, you'll soon get left behind.
I'm not saying the storyline moves fast, it doesn't. Quite the reverse, since all 13 episodes of a season focus on 1 single case.
It's the level of detail which the Wire goes in to that makes it demanding.
Also, the characterisation is second-to-none. There are no "good cops" and "bad cops". Just lots of shades of grey.
Streetslang is rife in the series, and the Wire assumes you are able to understand or at least get the gist.
The humour is black.
There is a lot of inter-departmental politics and in-fighting, which adds another dimension to the story.
Some episodes are low-key and character-driven. There may be no "action" as such, apart from the tension in the characters home lives, their own personal dramas, their struggles to try and do the right thing or just survive in a corrupt Police Department.
Other episodes might be more action based, with stakeouts, shootings, etc.
IMHO, the Wire is not suitable for people who just want to sit down, chill out and passively watch some cop drama.
You really do need to pay attention, actively think about what's going, and understand the characters and their foibles.
If you have seen Das Boot, the Wire is similar in some ways. Not very much action, but when it does happen it's brief and brutal. Long periods of cops trying to make progress against stupid paperwork and rules, and then inspiring breakthroughs as they close in towards their goal. Characters that are well developed and believable.
If you watch with a friend or partner who is similarly interested, I guarantee that you'll be having in-depth chats along the way.
The Wire makes you think.
10/10 from the BGG stable.