The Devil’s Mouth

Five friends, one last adventure before adult life closes in, and a Thai cave system with a name that should have been warning enough. The premise trades on the purest kind of dread, all cold water and narrow passages and a light that only reaches so far, then adds a hunter that is fast, silent and already down there in the dark with them. Claustrophobia comes first and the creature second, which is exactly the right order to build panic in.

Aimed squarely at viewers who find submerged spaces more frightening than any monster, and who enjoy survival horror where the group fractures as quickly as the air runs down. Expect a tense, physical hour and three quarters, with eroding trust doing as much damage as anything in the water. If tight spaces make your chest hurt, take this as a warning and a recommendation at once. It is a nasty, effective ride for a dark room and a good pair of headphones.