So in my place, there's these cliché as fuck drama shows that get aired by afternoon or evening, and the usual plot goes like,
1) The protagonist, as a kid, has her parents killed by some large company or organization who most likely hunted them down because they have some shit complicated business with the said company that kinda went down the drain, or that they have to be kept silent bc blah blah, basically, you get the gist of it.
2) The kid has this nice childhood friend (or people who are nice to her) and they hear about the tragedy, and they help keep secrets.
3) The kid swears some fucking revenge, lots of crying, etc.
4) The organization that killed her parents are way successful, and they're really well-known. There's usually scenes of parties, business transacts, and a whole lot of plastic-ness with other like companies that compete with them.
5) 10 years, or 7 years, or some shit number of years later, the kid goes back to society after literally disappearing (and miraculously didn't get herself hunted down by Police to put in a home for the orphaned) for that whole time. Childhood friend or nice aunt or neighbors are pleased, but notice something wrong with her; she's changed (cue dramatic music).
6) She carries out the revenge thing. Gets close to the company owner's son (who, not long after, becomes the company's owner himself because of a few circumstances that went according or not according to the protagonist's plans) in order to lower their defenses. Arouses suspicion from a select few people (usually the parent, or the person who has romantic interest in the male lead) except the guy himself.
7) Male lead falls kinda inlove with the female, if not entirely. Occasionally defends her, etc, and she literally fucking smirks behind his back etc etc. Childhood friend or nice people lecture protagonist on how this is not correct, but she has this strong conviction.
8) There comes jealousy from childhood friend if the chosen gender is male. This, though, is entirely optional and may not be present, but most of the dramas have it. Thus, he gets involved with some shady shit, himself, with the other company. Sells them out in order to get back protagonist to live a peaceful life or sth.
9) The series settles down for a bit, like a moment of fucking calm before the stressing storm that looks as if it's on repeat with every drama, only with copy-pasted faces.
10) Protagonist blasts into the building killing people. No, just kidding, sometimes they have another elaborate plan and the killing comes later, but the point is that, all the shit goes down by the time she comes back.
11) Her original plan involves killing the company people, but because she fell inlove with the male lead, she doesn't kill him. Also, childhood friend or nice people end up dying. Female lead and male lead either end up in a happy world, or the two of them journey together somewhere to realize stuff... where one kills the other, or where the series ends with a black goddamned screen after they show a gun on camera, or that kinda shit.
12) Basically, loved ones die, she disappears, worries nice people, returns with a 360° attitude change, revenge, kills people, kills nice people, realizes she fell inlove with male lead, doesn't kill him, shit endings.
If that isn't the whole plot of 91 days, then I don't know what else is.
((No drama series from my shit country were harmed in the making of this chapter.))