I don’t think it counts because the primary character was a ghost in-story, and not a delusion.
Sopranos had an imaginary girl that was supposed to be staying next door to Tony , think it was season 1.
That’s really a good question. It applies quite a lot to Fight Club.
When the Narrator was fighting Tyler Durbin in a street fight, what exactly did the other people see? What did they think of a guy beating himself up?*
And as you note, how much else shouldn’t we believe? Did they actually make soap from stolen body fat? Did the financial buildings really get blowed up (down)?
*It was at the point when the Narrator beat himself up in his boss’s (?) office that I realized Tyler was a figment of his imagination.
Unreliable narrators are a staple of storytelling. Yes, the audience is being lied to, the same is true of any story with differing points of view.
Yeah, they just saw the Narrator beating himself up. There is a small clip of it towards the end when the Narrator realizes it.
City That Never Sleeps (1953) - Hard-boiled story of cop Gig Young’s last day on the force. He’s having conscience problems over his plan to resign and leave his wife for a stripper (Mala Powers). He draws “Sgt. Joe” (Chill Wills, who also narrates as the “Voice of Chicago”) as his new - real or imagined? - partner.
*Meridan *(1990) - Sherilyn Fenn is in Italy to restore a painting. There’s an old lady she’s staying with who is not real, which is not revealed 'til late in this otherwise dull, but memorably sleazy flick.
Any version of Hamlet will contain the young Prince’s second “meeting” with the ghost of his father in his mother’s closet, an appearance many think is a figment of his imagination (your interpretation may vary). Unlike the ghost’s previous appearances where he was recognized by others, Hamlet’s mom does not even see the ghost, suggesting her boy is bonkers.
On Sesame Street the adults discovered Mr. Snuffleupagus wasn’t imaginary.
So, how would you have adapted the novel Fight Club, while maintaining the unreliable narrator plot twist from the end of the second act, without “lying” to your audience?
How about “The Wizard of Oz”? I suppose those characters were fantastical anyway.
Who says it has to be adapted? Whatever, if other people like this kind of thing, bully for them–but I want to be warned to stay away.
<perks up> Twin Peaks-era Sherilyn Fenn, you say? Sleazy, you say? Dat mean she get nekkid? 
If Psycho counts, then so does The Magnum, P.I. episode with Sharon Stone playing…twins.
And of course there was that terrible Bruce Willis movie Color of Night, where Jane March played a few different characters, which was supposed to be a shocking twist ending, but was instead so obvious that I was basically confused the whole time. “Why does Bruce Willis keep pretending not to recognize his girlfriend?”
I came here expecting to spend the thread poo-pooing such an easy plot twist.
But thank you for reminding me of the times it was used well.
Fight Club is brilliant.
Harvey is even brillianter.
I was thinking of mentioning that, but I wasn’t sure it fit the OP. The sister isn’t technically imaginary like Raines’ dead people. She can interact with the real world.
It’s established early on in River that his partner is imaginary.
In the movie “Jacob’s Ladder”, we learn at the end of the movie that the central character is experiencing everything as part of being in Purgatory and is a determination of his fitness for admittance to heaven.
So, everyone he encounters and everything he does from the fatal firefight in Vietnam is in “his imagination/Purgatory”.
Charlie Kelly imagined Barney during his “Pepe Silvia” rant: It's Always Sunny In Philadelphia - Pepe Silvia - YouTube
In the film version, at least, we have some independent evidence that Harvey is indeed “real”, opening doors and rewriting dictionaries and such.
There’s an American Dad episode where main character Stan has been gaining weight and trying to fight it off with the support of his family and fitness trainer named Zack that mocks Stan into exercising more and more. It develops that Stan’s weight gain is entirely in his head - the “weight problem” described by his family and coworkers is actually a dangerous case of anorexia, and Zack is entirely and similarly a product of that delusion.
Calvin & Hobbes comes t mind. Is Hobbes a real tiger when he and Calvin are alone, or is Calvin imagining Hobbes as being alive? Bill Waterson has never answered that question.
In that episode, “Oprah” is very much a real person, just not the real Oprah. Tina Fey’s character is heavily inebriated and has a case of mistaken identity.
I was trying to think of when this was clear. Late in the first episode???
Great series, btw.
(And she wasn’t the only one.)