The logline runs 54 words across two sentences, which works quite well for the longer-logline shape with a Mid Point Reversal, where “But when” marks the MPR turn. I would even consider rolling it into one sentence. But that’s personal preference.
The structure maps cleanly: setup, action 1, MPR, action 2. The only problem: Action 1 is not the main character’s action, which means that in this logline our MC only becomes active after the MPR, which is late.
The character description is another weak spot. “An American teen” gives geography but no psychology (“languid sheriff” or “self-centred weather man” shows what a character intro should do).
But the story is intriguing: The kidnapping, the protégé-then-bride grooming, and the mother-as-secret-lover discovery promise a layered revenge tail with real dramatic stakes, and the “use his methods to destroy him” payoff connects the grooming setup to the third act in a satisfying loop. A typo to clean: “her late mother’s his secret lover” has an extra “his”. The material is heavy (grooming of a minor, forced marriage), so a single tonal cue in the logline would help us place the genre.