Starring Anne Hathaway. Rated PG

The first hour of Colossal is packed with clever metaphors that use horror-movie tropes to explore the mysteries of human interactions. Some of this stuff is cleared up partway in, only to be replaced by a bigger question: why couldn’t the filmmakers come up with anything funny, smart, or thoughtful for the second half?

Anne Hathaway stars as Gloria (no last name given), a hard-partying Manhattanite just getting by on the largesse of booze-buying pals and her hardworking boyfriend (Dan Stevens). He’s finally had it when she comes home from yet another all-nighter, and she hightails it back to her old home in upstate New York—actually rural B.C.—to her spookily empty family abode (no explanation given). Help arrives in the form of an old grade-school chum called Oscar (Jason Sudeikis). Good news: he owns a bar and can give her a job. Bad news: he owns a bar!

A few nights after carousing with Oscar and his own readymade crew (Tim Blake Nelson and Austin Stowell, both underused), their drunken reverie is interrupted by news that a giant, Godzilla-like monster has surfaced in Seoul, South Korea. (Tokyo was already taken, as a suit from lawyers at Toho averred.)

This is enjoyably jarring, especially for something played as a routine indie dramedy until Koreans start getting crushed. The connection, as trailers tell you, comes when Gloria notices that her own personal tics are mimicked by that faraway gorgon. What this is supposed to mean—the collateral damage created by our own destructive traits or maybe the monumental size of our First World self-absorption—is left to our imaginations. That’s because the hard work of thinking it through wasn’t really done by writer-director Nacho Vigalondo, who gives us frustrating snack portions where the main meal should be.

As the only female character in the story, Gloria simply isn’t substantial or interesting enough to represent what the movie might or might not be saying about gender roles, violence against (or from) women, alcoholism, or the best use of Downton Abbey veterans. The worst thing about Colossal is that it feels so small.