Nacho Vigalondo’s Colossal, which stars Anne Hathaway and Jason Sudeikis, is a charming if slight cautionary tale about the monsters that people become when they drink.

Hathaway plays Gloria, who we meet just as her yuppie boyfriend (Dan Stevens, in a largely thankless role) throws her out of his apartment because she’s a drunken mess who’s “out of control.”

Broke and unemployed, she heads back home to New Jersey, where she crosses paths with Oscar (Sudeikis), an old classmate who inherited his father's dive bar where he entertains his two cronies, comic relief Garth (Tim Blake Nelson, funny) and plot device Joel (Austin Stowell, bland), while she stares longingly at the bottles behind the bar.

The intriguing hook at the center of Colossalis that Gloria's return home mirrors the return of a huge, Godzilla-like monster to South Korea, where it stomps its way through Seoul, killing hundreds of innocent people. It turns out that the monster is physical manifestation of a mental projection of drunk Gloria, who has the mysterious ability to control its movements when she stands in a public park at a certain time.

Filled with regret and horrified by the damage she has done, she cuts back on the booze until a giant robot shows up in Seoul, which is forced to rely on the monster for saving. The climactic showdown between Gloria and the evil robot is great, and the film ends with the perfect last line.

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While Hathaway carries her first genre movie with a sympathetic performance that showcases her quirky personality, her character takes a backseat during a dark second act when Sudeikis overpowers the picture with sinister conviction. One well-known critic compared Sudeikis' work here to that of Robin Williams in Christopher Nolan’s Insomnia, which is a spot-on comparison that makes sense by the time the credits roll.

But the true villain of Colossalis alcohol, which is responsible for Gloria's reckless behavior in the first half of the film. We all know someone who makes a mess of everything they touch as soon as they start drinking, and that's Gloria in a nutshell. The monster is an apt metaphor for that kind of destruction, and it's clever of Vigalondo to cloak this ambitious idea within a genre movie that itself feels like a riff on the meet-cutes and love triangles of a romantic comedy.

Like recovery, Colossalis a little messy, but it has more depth than its synopsis suggests.