The first time we watch Charlie (Nick Robinson) meet Harper (Emilia Jones) in Charlie Harper is not, as it soon becomes apparent, the first time Charlie has actually met Harper. It’s not even the second, or the third.

The pair have years of history already at this point. What exactly transpired between them, the rest of Charlie Harper fills out. By the time we circle back again to that meeting in the final minutes, it’ll play differently with the weight of everything we know now that we didn’t then — less confusing and more bittersweet, lighter and heavier somehow at the same time. But it also feels like too little, too late — a nice but underwhelming payoff to an otherwise frustrating romance.

The actual tale of Harper and Charlie is one we’ve heard a million times before already, or perhaps even experienced some version of ourselves. He’s intelligent but aimless, with no particular plans in life beyond partying with his friends. She’s fun and ambitious, with hopes of becoming a famous chef. When she moves from their small town to the big city (New Orleans) to pursue her dreams, he follows. But while she gradually blossoms in her career, he stagnates. Differences between them that had once appeared charming start to seem intolerable, and the eager promises they once traded give way to resentful reminders. Eventually, five years in, they break up.

Charlie Harper takes that straightforward arc and scrambles the timeline, so that the beats are organized not by chronology but by something like free association. Both halves of the couple narrate their memories from some as-yet-unseen point in the future, to two separate listeners sitting just offscreen. It’s an interesting approach, and a seemingly appropriate one for a film less concerned with how a relationship begins, or why one ends, than what to do with the memories once the thing has run its course.

So Harper reminiscing about her and Charlie’s first magical night together — “It felt like we’d always been in love. We just didn’t know what love would turn into five years later” — gives way to a scene of them bickering in the car some years later. That, in turn, jars an earlier memory of happier days in the same car, giddily documenting on camcorder their initial move to New Orleans.

Tom Dean and Mac Elridge, both making their feature directorial debut, demarcate the three eras of Harper and Charlie’s relationship — the beginning, the end and the aftermath — through thoughtful visual choices. The golden past always has the sheen of nostalgia, captured in the wide aspect ratio and softly grainy footage of a Hollywood classic. The end looks narrower, sharper, more naturalistic but less pretty. Meanwhile, most of the period after the breakup is cast in a bright white light, as if only now they’re able to see clearly.

But the showy structure overwhelms the unshowy story. All the frantic time-jumping and self-important narrating (Harper sets the tone in the opening seconds by tearfully asking, “Are you a nostalgic person?”) leaves little room for Charlie and Harper to simply breathe. While Jones and Robinson are fine in the leads — Robinson particularly nails Charlie’s ever-evolving combination of sweet and prickly — they aren’t given the space to relax into their chemistry, let alone to show us who these characters are beyond two sets of clashing personality traits.

The script, by Dean, has some lovely and poignant lines; one of my favorites likens a breakup to “watching time play backwards and the person you were closest with slowly becomes a stranger again.” But they’re outweighed by overly writerly touches, like a recurring conversation about a CD of Brenda Lee’s “Break It to Me Gently” that Charlie once burned for Harper, under the strict instruction that she not listen to it too much, lest the song “lose the thing that made it special.” Meanwhile, the score by Paul Leonard-Morgan, so gloomy I half wondered if one or both characters would end up dead, doesn’t so much enhance the film’s emotions as forcefully impose them upon us.

Only once we’ve gotten the full picture, near the end of the movie, does Charlie Harper finally start to come into its own. The film’s last scenes are its finest. Finally, the tricks of timing and the heavy-handed metaphors are cast aside — leaving us with a tender snapshot of two people trying, uncertainly but compassionately, to figure out what to make of a shared past but diverging futures. I wished it had been what the film was all along.