Scene summaries may contain spoilers
You hear a recording from a runner, Alison, who is using the app 'Run the World'; she's narrating her attempt at a route you are about to run. The running challenge is introduced by a recording of the route's creator, Elton Graysmith, who gloats that this route is too tough and will destroy you. Alison is unimpressed. She found this hidden route on an old forum. Eleven people have attempted the route and none have succeeded – or logged any runs afterwards. The route hasn't been flagged, and there's no other commentaries, so Alison is going to create her own. She is the 12th runner and you will be the 13th. Challenge accepted!
Alison reaches the first marker. It's been a fairly easy run so far, but with an unique feature: the next section of the run is revealed after you reach each marker. Not much of a challenge yet, Elton!
Elton slow claps sarcastically as Alison passes marker two and enters the woods. Alison explains that she found this route while looking for troll routes, like one which seemed normal at first, but when completed, the route map spelled out an insult. Usually they're removed from 'Run the World', but the one you're doing now is certified. Still, no-one has completed it. She has some juicy info but she'll tell you at the next marker!
Third marker down and now you're heading away from the beaten track and into some nettles. Alison isn't sure where this route is going. She explains how she came across the route. She'd seen it mentioned, but couldn't find it on the app, no matter what she tried. Then she got friended by Elton, who posted her the link with the message 'You asked for this'. It might not have been the best idea to do the route, but she's over halfway now.
The app starts to glitch and warp and Elton announces that there's no more map or announcer. Alison says that the path has vanished and that she has no phone reception. If she stops moving, everything is silent – no birds, or traffic, or woodland sounds at all. Elton interrupts to tell her to keep going.
Elton says that you've reached the end of the easy bit. Alison says that it's like hacking through jungle and there's the sound of snapping branches all around her. She wants to quit, but the app goads her by telling her she's going the wrong way. A branch snaps nearby and Elton screams at her to run.
Alison says that it's getting dark and it's hard to see anything. There's a horrible smell like rotting flesh and there are rogue voices playing in her app. She begs whoever uses the app to ignore this route. Get it flagged and deleted. If you hear this, get in touch with her parents to let them know what happened. The app announcer keeps telling her that she's going the wrong way. Suddenly, there's a snap of branches and Alison screams and sprints further into the woods.
Alison says that something attacked her and she's losing a lot of blood. It was tall and covered in moss. The app says that she has failed the route. Elton tells her to await her punishment. There's a roaring noise and the sound of a violent struggle. Alison's recording ends. As the app exits, you hear a roar.