Just watched the "Mirror Darkly" episodes of Enterprise, which should have just been titled "WTF?!"
It features the "Eeeevil" counterparts to the Enterprise crew, but unlike in TOS or DS9, there is no plot connecting them to the "real" crew: it's a self contained "Mirror Universe" story. These two episodes are notable for not having the Godawful opening song, opting instead to show us the evolution of the Evil Universe with a military theme music (no lyrics thank God) playing. Apparently in this Universe only Humanity is really evil; the Vulcans, Andorans etc are more or less the same as in the real 'verse.
Oh and you know how you can tell the women here are bad? They all wear BELLY SHIRTS! And Ta'Pol wears RED EYELINER because red = HATE! LOL.
I did like the plot, which involves Evil Archer learning of a ship from the "real" universe getting pulled into the Evilverse by the Tholians, so he hijacks Enterprise to go get it. Turns out the ship in question is the USS Defiant, from Kirk Era Star Trek, AKA 100 years ahead in time as well as from a different universe. Nonetheless Evil Archer and crew figure out how to fly it and decide to take over the Earth Empire. Oh and Archer dons the Kirk Era green shirt which seemingly gives him Kirk Swagger, which he doesn't display before the change of clothes.
I really like how this show and DS9 shows us a faithful TOS ship at a greater scale than TOS could show. Those primary colors really pop! Also the TOS era controls look a lot like Legos and the Scanner and targeting computers look like ViewMasters.
All in all it's an entertaining pair of episodes that make no sense at all, esp since in TOS the first time the Evil Universe learns of the "real" universe is when Kirk gets zapped there by accident. In the DS9 Mirror episodes it's made clear that Kirk was the first time the Mirror folk encountered "Goodness" and it had a major impact on their Universe. Oh well, I guess this was yet another parallel universe, different from the Mirrorverse shown in TOS and DS9.
Now into the home stretch!