I'm not particularly a fan of Persona-based anime, although I haven't seen many of them and they're not made for me anyway because I haven't played the games. The Persona games go back to 1996 and they're a spin-off of the Megami Tensei game series that debuted in 1987. Of the ones I've seen:

(a) Persona 4: The Animation (2011) was a bit impenetrable to game newbies (i.e. me) and had an annoying bear character who said "bear" at the end of all his sentences. The second half was better than the first, though.

(b) Persona 4: The Golden Animation (2014) I found more likeable, but still a bit clumsy.

This is Persona 5, though. The game's apparently excellent, with record-breaking sales and lots of critical acclaim. In it, you play a high school student who's falsely accused of assault and transferred to a school called Shujin Academy. There, you and your classmates will learn about your Persona powers and become a vigilante group called the Phantom Thieves of Hearts. You don't beat people up, though, but instead pull the malevolence from their hearts and make them better people.

This is a standalone anime special that aired on TV as publicity for the game. There's also going to be a full anime series in 2018.

Anyway, as before I'm pretty sure it'll be more meaningful if you've played the game. It's a bit weird and under-explained, but I'm sure someone who's already invested in this universe would think it was great. I could imagine finding it cool. (I didn't, personally, but it seems like the kind of dark, atmospheric, semi-gothic thing that has lots of cool potential.) Our heroes have the power to change into superhero fetish outfits with animal half-masks when a train goes past them on the underground station platform. Doing so will also suck them into a magical fantasy realm that looks like the inside of someone's heart, with tentacle-like veins, lots of darkness and bulgy red bits... but also big chains and train tracks. This is quite fun to look at. Our heroes will have magical fights there against baddies.

We're even told what this place is, i.e. "the other reality given shape by human hearts". Well, that explains everything.

There aren't enough girls. There are five baddies (thieves) and five goodies (Phantom Thieves of Hearts), but both only have one token girl. Mind you, one of those goodies is a talking cat.

It's okay. I didn't really respond to it, personally, but that's probably just me and my lack of familiarity with the games and with Persona in general. I don't think I really connected with the goodies, who seem to have popped out of nowhere and didn't really have any characterisation, backstory or motivation that I noticed. They exist. They do their thing. They're pretty. However there's a perfectly reasonable storyline about the thieves and their young lockpicking boss, who of course will be targeted by our heroes. For a one-off episode, I'd say it's pretty good. There's nothing wrong with it. It does the job. There are hundreds of standalone anime OVAs that completely fail to tell a memorable story at this kind of length, but this episode was watchable. Just be warned that I thought the heroes were basically empty shells of cool, although perhaps that's not so surprising given the shortness of the project. The baddies are the ones who came across as human. (Certainly not good people, but definitely human...)