In this atmospheric thriller, a National Guard Squad ventures into the bayou to practice some maneuvers. (This is a corollary to my longstanding “I don’t fuck with the woods” position: I also don’t fuck with swamps.) The unit is roughly 70% chucklefucks, 10% men traumatized into near psychopathy, and 20% world-weary sanity, as represented by the excellent Keith Carradine and Powers Boothe.

It’s a training exercise, so crucially, most of their ammo is blanks. The only reason they have any live rounds is because one man smuggled them along in case he saw the chance for a little hunting. In another, more action-packed thriller, the lack of real ammunition would just be an excuse for the men to spend most of their time in badass hand-to-hand combat. Here, it’s a devastating blow. These aren’t highly-trained special ops forces; they’re not professional military. They’re basically prickly, out-of-their civilians, ones who are governed more by uneasy, fluctuating group dynamics than by proper hierarchy.

Maybe none of that would matter, if the exercise went according to plan, but it doesn’t. The men speed up their training exercise by stealing canoes from some backwoods Cajuns, who catch up with the Guardsmen while they’re on the river. One of the Guardsmen thinks it’s the height of hilarity to respond to their yells of protest by firing at them wildly. He’s firing blanks, but the Cajuns, of course, don’t know that. They respond with real bullets–and kill one of the Guardsmen, setting off a kind of intimate swampland guerilla warfare. They can’t afford to have any of the Guardsmen get out alive, and the Guardsmen can’t stop escalating things. Aggressive stupidity and an unearned sense of authority run headlong into local knowledge and community power … but it’s power that only holds as long as they’re in the middle of nowhere.

The suspense escalates steadily, and Walter Hill excels at creating a muggy dreamlike intensity that’s perfectly wedded to the landscape. It really feels like these men have stumbled into a pocket world–part-Deliverance and part-Les Blank documentary–that works by its own hidden rules. And while Carradine and Boothe play characters who are more capable than the rest of their companions–and more able to realize that they’re out-of-their-depth and at a disadvantage–we can easily believe that they still won’t be able to make their way out. It all comes together as a moodily gripping film that’s well-paced, distinctive, and fully realized.

Southern Comfort is streaming on Tubi.