Splinter

Polly Watt and her grad-student boyfriend Seth Belzer drive into rural Oklahoma for a low-budget anniversary camping trip. The tent collapses in their hands, Seth admits he doesn't really know what he's doing, and they bail on the camping plan — heading back toward civilization on a dark county highway to find a motel instead.

On a remote stretch they're flagged down by what looks like a stranded driver. It's Dennis Farell, an escaped convict, and his addict girlfriend Lacey Belisle. Dennis pulls a gun and takes them hostage in their own car, ordering Seth to drive. Lacey is jittery, sweating, and clearly going through withdrawal; Dennis is sharper and harder but visibly tired of running.

Driving the back roads, they hit something — a deer or coyote in the highway, half its body unfamiliarly black and spiked, twisted around itself in ways that don't read as ordinary roadkill. The tire blows out from running it over. Dennis spots a single dim light off in the distance: a one-pump gas station with a small attached mini-mart. He orders Seth to limp the car in.

The clerk isn't behind the counter. Seth goes looking and finds a man named Teddy in the back, slumped against the bathroom wall, ankle pierced through with a long black spine. Teddy is dead. As Seth backs away, Teddy moves. Not normally — joints bent backward, the spine driving the body's motion as if pulling strings. Spines erupt across the skin. The thing inside him is a parasite. Teddy lunges; the four lock themselves into the front of the mini-mart and slam down the bulletproof rolling cage that separates the cashier area from the rest of the store.

Through the wire mesh of the cage they watch the thing test the boundary. Pieces of it move independently — a severed hand finds its own way across the floor. Dennis loses his composure for a moment but recovers. Seth, a biology grad student, starts watching. The parasite is drawn to anything warm: a propane heater, a recently-touched soda can. It loses interest in things that have cooled. Heat is the signal. The infected aren't possessed — they're remotely puppeted by the splinters, each fragment a relay.

A sheriff's cruiser pulls into the lot in response to an earlier APB. The group waves him off frantically through the glass, but he comes inside investigating. The Teddy-thing — now mostly limbs and trunk fused into something less recognizable — catches him in the gas-pump shadow. The sheriff is converted in seconds. Now there are two of them outside the cage, and what was once a sheriff's gun is no longer aimed by a sheriff.