![](https://image.tmdb.org/t/p/original/o3PJPcTY40mUkj96P6wwhTIN9Rf.jpg)
![](https://image.tmdb.org/t/p/w200/n5aMoI6AZLJzUoNbjMj0P60EYMJ.jpg)
Once you get in, you can't get out.
Four teenagers at a British private school secretly uncover and explore the depths of a sealed underground hole created decades ago as a possible bomb shelter.
Four teenagers at a British private school secretly uncover and explore the depths of a sealed underground hole created decades ago as a possible bomb shelter.