Dabbling in the mirror universe is always fun, and this episode certainly lacks nothing in the raw entertainment category. But it’s also a thing of blown opportunities. Here, we had a chance to see Sisko come face to face with a potentially tear-jerking plot arc–and what should have been a home run for our favorite baseball junkie was only a base hit.

That’s not to say that “Through the Looking Glass” doesn’t have its bright moments–actually, there are plenty. Intendant Kira is sultry, savage and conflicted as usual, and the mirror versions of Rom, Dax and Bashir are just as amusing as ever. The actors have got to love having a chance to stretch different muscles, and it shows. We even get a cameo from Voyager in the form of Tuvok, who the episode smartly chooses not to emphasize. That isn’t because there’s anything wrong with Tuvok, by the way, but the writers were bright enough to realize that Sisko wouldn’t recognize the man, and special emphasis or some expository scene would have been unnecessary. It’s a case of less being more.

But my umbrage concerns everything away from the action (which is well-realized and gripping). In particular, I just can’t grasp the lost opportunity of all that emotional fallout Sisko should have when he reunites with his wife, Jennifer–even if her mirror version is a misguided Terran collaborator. Maybe these two needed more screentime, or maybe the writing of these scenes could have been sharpened, but the drama and substance of those moments were conspicuously absent. The writers in this case did action well–but Ben should have cracked, even if only a little, over meeting Jennifer. I know if I lost my wife, then met a version of her elsewhere, I’d be a wreck.

It also has to be said that I don’t buy Jennifer for a second. The performance is to blame, and I’ll leave it at that.

Finally, this is yet another mirror universe crossover by prime universe characters with no ramifications. Given the existence of this parallel plane, shouldn’t there be more consequences for crossing over–and more precautions in place to make sure it doesn’t happen? When mirror O’Brien can get into your command space with ease–and I don’t buy that he’d be familiar with DS9’s security and systems–someone needs to be reprimanded. Where was our ever-vigilant Constable?

And why, pray tell, would Sisko risk his life and career directly interfering with the mirror universe, ostensibly just for the chance to save someone he cared so deeply about…and then leave her behind? Wouldn’t he have been tempted to bring her back, even if that cost him his command? I mean, he knows her presence in the mirror universe, and her skills, have made her a very public target.

The show doesn’t deal with any of these hanging issues. There are no costs associated with Sisko’s meddling. He’ll bounce back next week, I’m sure, carrying no baggage or turmoil with him. And how about his experience with mirror Dax? I shouldn’t ask.

Those hidden costs of interference are something TNG was obsessed over. It did a better job with them in comparison to DS9 (at this point in the show’s run). There were entire episodes devoted to the price of altering the course of a society’s evolution. Here? It’s lip service we seem to keep paying to the prime directive.

I know the show can do better.

Rating: 3/5 stars.