The chicks were hot, but I don't remember understanding much. I think the twist was the actresses swapped roles/identities/parts/etc. halfway through or something.
It's been awhile since I've seen it but the way I remember it is more like most of the movie wasn't real, that it was just an exaggerated narrative or more likely a dream, which would really help explain the "dream like" and weird feel the movie has throughout. And the dinner scene towards the end is kinda the key scene where it's all revealed. The main chick moved to LA with the intention of being a big Hollywood star, she ended up meeting the other girl Camilla or something like that but she goes by Rita in the "dream" parts. They fell in love and eventually that girl broke her heart and left her for that director dude. So she's just a washed up actress who never made it, a junkie, and the woman she loved broke her heart and the movie is really all just an exaggerated metaphor for that. After that dinner scene she decides to hire that hitman to kill her. And then the movie nseeming ends with her commiting suicide after doing that? I'm not 100% my memory is a little foggy on it and I've only ever seen it once. but I think it's supposed to be sort of like Nocturnal Animals where the novel portion of the movie isn't real but it's an exaggerated metaphor got his relationship with that woman falling apart.
But there's tons of stuff about Mulholland Drive I don't remember the answer to like what was up with that monster chick that the dude saw behind that diner at the beginning? Who we're thinking seemingly government/shadow organization dudes? An exaggeration of movie executives? What was the meaning of the blue box and key? Etc. I should probably watch it again but jfc the movie is so terrible up until the ending and the "twist". I mean the acting, dialogue, and just everything sucks so hard. I don't care if it was intentional or not, I don't know if I can sit though like an hour and 45 mins of shit just to get a good ending. ---
"You need to lay off the peanut-butthurt and u-jelly sandwiches" - Neon Octopus