An illustrious British boarding school becomes a bloody battleground when a mysterious sinkhole appears at a nearby fracking site unleashing unspeakable horror.
| Actor | Role |
|---|---|
 Finn ColeDon Wallace | Don Wallace |
 Asa ButterfieldWilloughby Blake | Willoughby Blake |
 Hermione CorfieldClemsie Lawrence | Clemsie Lawrence |
 Simon PeggMeredith Houseman | Meredith Houseman |
 Michael SheenThe Bat | The Bat |
 Nick FrostWoody Chapman | Woody Chapman |
 Tom Rhys HarriesClegg | Clegg |
 Isabella LaughlandKay | Kay |
 Kit ConnorWootton | Wootton |
 Jamie BlackleyCaspar de Brunose | Caspar de Brunose |
 Margot RobbieAudrey | Audrey |
 Jo HartleyBabs Wallace | Babs Wallace |
 Jane StannessMatron | Matron |
| LLouis StrongSmudger | Smudger |
 Jassa AhluwaliaYuri | Yuri |
| CCory ChambersBello | Bello |
| AAlan DrakeButler | Butler |
| CCharles EvansMikey | Mikey |
| CCharlie FitzherbertTomkinson | Tomkinson |
 Alhaji FofanaChibwe | Chibwe |
 Hanako FootmanPoppet | Poppet |
| GGary GoldingHedger | Hedger |
| RRohan GotobedScholar Bartlett | Scholar Bartlett |
 Nick KellingtonThe Beast | The Beast |
 Alex MacqueenLambert | Lambert |
| LLevi MasoetDr. François | Dr. François |
| NNeil PendletonRed Dreads | Red Dreads |
 Max RaphaelHargreaves | Hargreaves |
| JJames WoodroffeTeddy Chapman | Teddy Chapman |
| JJoshua SquireOlympus Boy (uncredited) | Olympus Boy (uncredited) |