BBC DRAMA Vigil follows the investigation into a dead serviceperson aboard a Royal Navy submarine.
The six-part series is by the makers of Line of Duty and Bodyguard.
Is Vigil on BBC One based on a true story?
Vigil is written and created by Bafta-nominated writer Tom Edge who is known for The Crown.
As much as the gripping story will feel like it could be true, it is not based on real-life events.
Speaking at a press event for the show, Tom said: “I think over the next 10 years submarine warcraft is going to dominate in a way they haven’t been thought about for a while.”
The show will explore the ethical questions raised by the existence of a nuclear deterrent submarine programme, and the spiralling costs of submarines.
However, the peace camp in Vigil is inspired by the real-life Faslane peace camp.
The camp is located next to Faslane Naval base in Scotland - the home of the Trident nuclear programme.
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What is Vigil about?
A mysterious disappearance of a Scottish fishing trawler and a death on-board a Trident nuclear submarine bring the police into conflict with the Navy and British security services.
DCI Amy Silva leads an investigation on land and at sea, with the action cutting between the investigation in Glasgow, Scotland and the unfolding drama at sea.
She will look into a conspiracy that threatens the very heart of Britain’s nuclear deterrent.
Surrane Jones is joined by Line of Duty star Martin Compston, who plays an underwater expert.
When does Vigil start on BBC One?
The first episode first aired on August 29, 2021.
Episode six of season one will air TONIGHT at 9pm on BBC One.
All episodes will be made available on BBC iPlayer at the same time as they're broadcast.