You are mons living at Sara Weatherby's sanctuary for abandoned mons,

Your friend Arachne, an artist mon owned by a friend of Sara Weatherby, is going to have her art featured in an exhibition.

Contains spoilers for an upcoming campaign, obviously

 kinda wish we could do more unsanc, but with the ability to introduce our characters. Or maybe just mine; I really want to try out Arachne.
I don't think I'm capable of GMing (I feel like I just struggle so much to get my head around it), but I have this daydream of an art opening of a new painting technique developed for this futuristic world: steganographic neopointillism.
Tiny colored dots, now reminiscent of pixels in modern society, used to paint a scene, but there's more. The exact colors and styles also program a sort of experience. A painting of a pleasant day at the beach with the data the smell of the sea, the feel of the cool wind, and the joy of being able to relax...
That was Arachne's contribution to the gallery, at least.
For the sake of the experience, mons are recommended to turn off some of their visual input sanitation so as to experience the paintings in full, as they are generally programmed to block visual attempts at what is, essentially, a hacking of their other senses.
This, however, made the event a great opportunity for Ann, who would potentially be able to free thousands of high-society mons just by changing one aspect of a single painting: having it be a be a pleasant day at the beach, with all the accompanying pleasantness for the senses, because you are a free mon.

Unfortunately, someone beat her to the punch, coding a more devious message: a pleasant day at the beach because the humans are dead.

It'd give mons on both sides of the coming revolution to try and track down the true culprit before the death of a new artstyle and a potentially very deadly retaliatory crackdown against the resistance (or perhaps, more specifically, Weatherby, if the true culprit's intent turns out to include implicating her) following the potential death of multiple high-profile members of society.

Necessarily procedurally generated - density limitations

An art exhibition in Tranquillity Town. Arachne is presenting her art, along with several others, designed to be appreciated by both humans and mons. Most of the mons viewing will of course be companion mons or pet mons (aside from special art-related mons). The paintings presented are using the same mechanism as uMon's visual update patch system (used to capture wild mons) to encode sensory experiences. This is not supposed to be a security risk normally; uMon has given it the go-ahead because of the intervention of politically well-connected patrons. Reportedly, Marcus Jobe himself intervened to approve it, being a patron of the arts. Another executive of the Great Corporations, Arya Tang the president of infoTronics, will be a guest judge.

Arachne invites some mons from the sanctuary to come as well. Ann is unavailable, as she is currently out of the area, questing for replacement parts for her non-self-replicating components. The party sets up for the exhibition. They see the bad painting being set up as well; the jailbroken mons, having been patched by Ann against nonconsensual re-use of the umon patching mechanism, are surprised to get requests to be patched when they see the painting. (Normally the mon would not get any notification.) Arachne can analyze the art to extract the patch, though she is not able to fully understand its contents, it appears to contain an image-recognition module that can be tested against images, and convey a lot of angry feelings in response to the module.

They can deal with this however. If they don't, unprotected mons who see the painting will feel incredibly angry at Arya Tang, and one or more of the more volitile ones is bound to attack her during the show.

Who did this: Rogue Modder's Union members, pressured by Jobe, to eliminate Tang, a rival who is opposing him on the infoTronics board. uMon security will swiftly kill the mon artist if the plot is exposed, to make sure he can't talk.

Artist: A Kosemon sport mon, modded for art (both a project and an artist) - owned by a modder's union member, Yan.

Beaker, Arachne, Utility Mon, Lily, Zoey, Kosemon ‽

Beaker - A parrot-like Loromon. Abandoned by her owner after the species was nerfed by uMon a few years ago, she came to live at Weatherby's mon sanctuary. She is pugnacious, like many sport mons, but very loyal.

Cory - A humanoid companion mon, a type of utility mon intended as a personal valet or social companion. He is about a meter tall and somewhat elfin-looking. He was owned by an old lady for many years; when she died, her heir gave him to the mon sanctuary.

Zoey - A pet mon, in the form of a miniature elephant. Zoey belonged to a Modder's Union member who made her something of a demo for his capabilities, which included enhanced intelligence. She is trained to appraise art.