When I leave a theater after a movie screening, I always have some ideas about what I’ll say about it in my review. I’ll sit in my car for a couple of minutes and dictate some ideas into the Notes app on my iPhone, and if my wife is with me, we’ll discuss it on the ride home.

I can’t remember exiting a screening with no idea what I might say about it. But that’s exactly how I felt after viewing “I Saw The TV Glow.” The second half, especially, made me wonder if I had accidentally taken ketamine earlier in the evening, because I had no idea what was going on.

It was a sensation akin to watching the last twenty minutes of Stanley Kubrick’s “2001: A Space Odyssey” — the part where astronaut David Bowman flies through what seemed in 1968 to be an LSD-infused light show, followed by scenes with an old man in a weird house. I’ve never heard anyone give a satisfying explanation of that, and I doubt I can provide one for this.

But I’ll give it a try.

“I Saw The TV Glow” starts off innocently enough in 1996 with a seventh-grader named Owen (Ian Foreman), who sees a promo for a sci-fi/fantasy show called “The Pink Opaque,” which airs Saturdays at 10:30pm on the Young Adult Network. It revolves around two girls who meet at camp and have some supernatural connection that allows them to fight whichever monster has been sent that week by the show’s uber-villain, Mr. Melancholy.

Owen is more than a little intrigued, and longs to see it, but his parents insist he’s in bed by 10pm, so that’s not going to happen. Then he meets a ninth-grader named Maddy (Brigette Lundy-Paine) who’s reading an episode guide to the show. He befriends her and, on the pretense of sleeping over at a friend’s house, he goes to Maddy’s instead to hang out and watch that week’s episode. As kids his age frequently do, Owen immediately becomes obsessed with the show and happy to have Maddy to discuss it with.

The movie jumps forward two years (with the older Owen now played by Justice Smith), but he hasn’t seen any more episodes because his parents still impose a strict bed time. Fortunately, Maddy records each episode on VHS tapes and leaves them for him to collect at school. He takes them home and pores over every pixel.

Now here’s where we get to the part of movie I can’t put into words. Owen’s and Maddy’s preoccupation with the mythology of “The Pink Opaque” starts merging with the bland alienation that is their suburban life. It explores themes of teenage insecurity, sexual identity, and gender dysphoria amidst a plethora of surreal images even David Lynch didn’t consider when he made “Twin Peaks” (e.g. did that guy just stick his head and neck inside the TV screen?).

In “I Saw The TV Glow,” writer/director Jane Schoenbrun has created a story which, the deeper it goes, seemingly slides off the rails for long periods and barely ever pulls back into normality, however defined. I don’t have any complaints about the technical aspects of the movie, or the performances of its leads, or the clever way Schoenbrun shows clips from the TV show within the movie.

Still, with its color scheme full of pink and a plot that’s more than a bit opaque, I can’t give “I Saw The TV Glow” more than a 3 out of 10. Opens in theaters today.