By Bob Grimm

Writer-director Alex Garland, often a purveyor of excellent sci-fi and horror (Annihilation, Ex-Machina), drops a full-blown cinematic grenade with Civil War, a hypothetical look at an America divided during a second civil war. It’s also a look what lengths the press will go to in order to get a story. This is not a happy movie by any means.

Kirsten Dunst, in one of the best roles of her career, plays Lee, a photojournalist covering what could be the last days in office of a tyrannical three-term president (Nick Offerman in a small but effective appearance), during the tail end of a divisive Civil War. California, Texas and Florida have seceded; they’ve combined their military might—and Washington, D.C., is in their crosshairs.

Lee and colleagues Joel and Sammy (Wagner Moura and Stephen McKinley Henderson) are on their way to D.C. to try to get an interview with the troubled president. Jessie (Cailee Spaeny), a photojournalist wannabe, tags along.

The movie is largely good, but the plot takes its characters down some predictable routes that had me rolling my eyes a bit. Also, the ending is kind of ridiculous—well-filmed, but ridiculous.

Most of the action is top-notch, and some of the scenarios are genuinely horrifying; overall, Civil War is effective and quite memorable.

Jesse Plemons has a cameo in the most memorable and chilling scene. I won’t give too much away—but when he shows up onscreen, get ready.

The timing of Civil War, released when the country is going a little crazy politically, makes the film feel less hypothetical and more possible. A divided U.S. in violent conflict feels less fictional than it would’ve, say, 15 years ago. In fact, much of this feels quite realistic. According to Mr. Garland, the United States is in a lot of trouble.