When starlet Anne Baxter preyed on aging stage legend Bette Davis in “All About Eve,” did anyone figure that paradigm would eventually shift to middle school? Every two years we chop down the last teen star so that a new one can rise in the sunlight. You know Stewart and Lindsay and Fanning and Fanning, Knightley and Woodley and Ronan and Breslin. But do you recall, the greatest teen-actress of all?

Would it be Chloe Grace Moretz, who opens this week’s superior teen romance “If I Stay?” In the long scheme of moviemaking, from the Lumiere Brothers to “Interstellar,” “If I Stay” doesn’t amount to much. But I wish more small films would not amount to much with the same affection for the craft and the story.

The R.J. Cutler film, split into two side-by-side parts, is an appropriately swoon-heavy take on the Gayle Forman Y.A. novel. The first part is a teen-friendly Romeo story, between Beethoven-minded musician Mia (Moretz) and her manic pixie dream guitarist Adam (he’s not a vampire—he’s just in a band!).

The second part is a hospital melodrama that leaves her family members dangling in peril (every teen romance, come on, needs a big, cheesy, emotionally manipulative plot device that makes the heartache burn). In the wake of family tragedy, Mia must decide whether to stay in Portland with her boyfriend, attend Julliard, or move on to a different phase of life.

As a shy cellist, Moretz finds a nice, normal, recognizable spot for a heroine. She isn’t a damsel in distress like Bella Swan, but she doesn’t need to bowhunt other people to prove it, either. She has a relatably nerdy teenage obsession that isn’t sci-fi or supernatural. This is the rare movie character that doesn’t scream “movie character,” and the seventeen year-old star handles her with admirable simplicity.

Moretz isn’t alone, she is at the center of a solid ensemble. As the hubba-hubba boyfriend Adam, Jamie Blackley appears pre-pressed for spectacular death by cuteness. But I liked how he handled the role—liked the music, liked the chemistry–although I don’t know what he’s going to do with a guitar band these days. Elsewhere, Mirelle Enos and Joshua Leonard do a serviceable job as ex-hipsters-turned-responsible-parents—because every Gen Xer spent the years 1990 to 1998 in an ear-damaging band (alongside Ethan Hawke in “Boyhood” this appears to be the new movie cliché.). As Gramps, Stacy Keach–Stacy Keach, where have you been, Big Guy!–steals his scenes with a pair of warm monologues.

The cinematography, by John de Borman, should be commended for bits of excellence. Several hidden visual treats wait for the close viewer. These include an unusually eloquent car crash, suggested by a line of smoke rising into an icy sky. Afterward, the camera walks slowly alongside Moretz through the busy emergency scene, even circling her twice. The shot is showy and self-conscious, true, but there are a thousand boring ways to do the same thing. The light and shadow (such as during a moonlight hootenanny) has moments of superiority–above what you would expect from a small production.

To close out, let me ask this question: when did Hollywood romance become kids stuff? Through the nineties, big, aching adult romances with epic sweep were awards mainstays. Watch cable and you will catch films like “The Last of the Mohicans” or “The English Patient.”

The last similar film was perhaps “Atonement” seven years ago. Since then, intense romance has been focused on teens (“Twilight,” “The Fault in Our Stars,” even “Moonrise Kingdom”). In the Apatow Years, adult love stories have become cynical and comic. Something like “This is 40” is about the best grownups can hope for.

So when and why did falling madly in love go away with the learner’s permit? There is something distressing in the movement of romance from adult wishfulness to teen fantasy. “If I Stay” might take a beating from some middle-age reviewers sick of love and on patrol for anything that might spark hope. That’s a shame, because in this case I think it’s the kids that get it.