In 2020, the most ambitious drilling project in history is under way. Dr Nasreen Chaudry and her team have reached 21 kilometers into the Earth's crust - but something is stirring far below. Amy Pond discovers there's nowhere to run when you can't even trust the ground at your feet.
| Creator | Sydney Newman |
|---|---|
| Actor | Jodie Whittaker, Mandip Gill, John Bishop |
| Country | Canada, United Kingdom |
| Production | BBC Cymru Wales |