Credit: Courtesy of Neon

Two seemingly incongruous categories โ€” the small-scale romantic doodle and the rampaging-creature feature โ€” are brought together in Nacho Vigalondoโ€™s Colossal, a film that never really fulfills the potential of its adventurous premise. This monster mash-up argues the opposite of what Humphrey Bogart declared in Casablanca: The problems of two little Americans are of monumental importance in this crazy world, or at least on the other side of the globe. But what could have been a barbed look at extreme narcissism, whether individual or national, is reduced to that mildest of metaphors, the road to recovery.

In that respect, Colossal, Vigalondoโ€™s fourth feature (and the first of his that Iโ€™ve seen), isnโ€™t too far removed from Jonathan Demmeโ€™s Rachel Getting Married (2008); both films center on a substance-abusing mess played by Anne Hathaway. In Demmeโ€™s movie, the manipulative protagonist excels at toxic femininity, insisting that the whole world revolves around her. That concept is made literal in Colossal, in which the drunken antics of Hathawayโ€™s Gloria have calamitous effects on the citizens of Seoul, terrorized by a behemoth beast that, we soon learn, is the boozerโ€™s avatar.

Kicked out of the Manhattan apartment she shares with her imperious boyfriend (Dan Stevens) for one tipple too many, Gloria retreats to her hometown, a vaguely leafy Anywheresville that hints at the generalities to come. She reunites with Oscar (Jason Sudeikis), an elementary-school pal who offers the jobless woman โ€” Gloria was let go from her online magazine gig for a never-disclosed misjudged play on words โ€” a few shifts at his bar. Unable to resist the PBR that surrounds her, Gloria tunes in to the news the next day to discover the consequences of her face-planting: โ€œI killed a shitload of people because I was acting like a drunk idiot again.โ€

Soon Gloria and her mammoth manifestation have a nemesis: Oscar and his own outsize alter-ego, a giant robot that further menaces South Korea. Their battles, at home and abroad, grow bloodier when the initially genial local guy, who never left the neighborhood, reveals what a petty, possessive bottle-abuser he is โ€” a noxious misery beyond the ken of Sudeikis, incapable of conveying self-contempt. That inability to be fully contemptible or even mildly dangerous also hampers Hathaway, a performer who always seems so eager for audience adoration. Engaging ideas bubble up every so often in Colossal, a film that carries out magical thinking to its extreme. But the audacity of its conceit is inexorably tamed, becoming an all-too-familiar lesson on saying no.