So just browsing what was on Hulu I remembered oh yeah, I forgot to watch more than the first season of Legion. There's only the 3 and the last is pretty short, so catching up didn't take long, and wow, what an astoundingly weird show.
TECHNICALLY, it's based on something but it basically never references a single character, setting, or event from it (if you're looking out there's like, 5 vague nods in the whole series?) and the protagonist's whole deal is basically rewritten, so basically it's a fully original thing you get to watch and then get curious about those notes in the credits and look it up and sputter indignantly that you had no idea.
Beyond that, it's basically about some guy who is initially in a mental institution, gets busted out by weirdos who tell him that he's not actually mentally ill at all, and all those voices in his head are actual people whose thoughts he's hearing because he has psychic powers... and then a few episodes later they all apologize because turns out in addition to having psychic powers, he actually does have some really severe mental illnesses, a good chunk of the voices he hears are just good ol' fashioned schizophrenia, and getting him off those medications was a pretty terrible idea in hindsight.
And past that it's just super weird. You know how other shows in the general genre fiction field will have that one episode set in a surreal dreamscape because there's a nightmare demon or psychic weirdo or whatever screwing with the whole cast? That's basically just every episode, and it's always at least mildly ambiguous if like, a random cow or space horror in the hallway is a hallucination, a psychic projection, or there's just randomly a cow or space horror in the hallway because these characters have more than just the one thing they're dealing with, and the protagonist in particular isn't going to start asking questions about it because, again, kinda the whole point of the show is to have a character with something approaching actual schizophrenia, where someone has vivid hallucinations and learns to mask this by being unusually calm, rather than "having multiple personalities" as was his deal in the source material that technically exists and hence the name I guess.
Also there's this weird little quirk where nearly every character on the show has, for lack of a better term, weird gender stuff going on?
- We've got a character named Lenny who was originally planned to be a 40-something sleazy dude but was then cast as a woman who was adamant that wherever possible she still be written as a 40-something sleazy dude.
- The main character's love interest has body swapping powers working on an involuntary skin-contact basis, so, yeah.
- There's this brother/sister pair who have this honestly really complicated and hard to explain thing going on where they're sort of a single person and the sister is inside the brother's body most of the time and eventually there's this bit with how if she's going to be out full time there's a bunch of basic life stuff she has to learn and it's... honestly much easier to say they're a giant trans metaphor and leave it at that.
- The second season introduces someone who seems to use he/they pronouns and speaks through a large collection of android women who look like 80s music video backup dancers except they all have really prominent mustaches.
It's also weird now that I think about it that not only are there a lot of Akira-style violent character deaths and a lot of all the characters present breaking spontaneously into song, those are usually concurrent even.
On the downside, it gets pretty bleak overall, gets really uncomfortable in places with self-harm/suicide imagery, and does particularly torturously nasty things to... most women in major roles.
It's also hard not to directly compare this to Umbrella Academy, which... to be fair I think was directly inspired by this? At least in show form?