Warning: This article contains spoilers for the first episode of Vigil

Viewers of new BBC drama Vigil were left utterly shocked after a huge twist 10 minutes into the first episode.

The series stars Suranne Jones as Detective Chief Inspector Amy Silva, who must investigate the death of a crew member on board the Trident nuclear submarine HMS Vigil, along with colleague DS Kirsten Longacre, played by Game of Thrones' Rose Leslie.