As BBC thriller Vigil returns to our screens for its third season, creator and writer Tom Edge has revealed the central question at the heart of not just this season, but the whole show entirely.
The series has changed location for each new season now, and focused on an entirely new form of warfare, with the first run focused on a nuclear-powered submarine, the second on drone technology and this third on the battle over control of the Arctic.
One thing which has remained constant is the presence of Suranne Jones's Amy and Rose Leslie's Kirsten at the centre of it all, but speaking with Radio Times, Edge noted that the series has always been about conflicts of loyalty.
When asked what he hopes viewers take away from the third season of Vigil, Edge said: "I hope that when audiences reach the end of this season, that the real conflicts deriving from that central question of loyalty come to the fore.
"That is where I think we have the most to say – about individuals and their sense of right and wrong, their understanding of justice, whether that is a kind of an outcome that they can live with morally, as opposed to the letter of the law being imposed and worked through, and the complexity of our relationship, both with those who are on paper allies and those who, on paper, are in opposition to British interests or alliances."
He continued: "That's where we get to really dig into this. The show relies on its shades of grey, in between car chases and rifle shots. That's where I think some of the most interesting questions are explored.
"We've never wanted to make a show where the bad guys are determined purely by which flag they fly, as it were, and I think this season offers us offers us a lot in terms of situating individuals in a very compromised position of being asked to act in the national interest, but also, sometimes having to make decisions where a kind of justice that they feel is appropriate might conflict with that.
"And I think we see that on all sides of this. So hopefully, between where we begin and where we end, we take the audience on that journey."
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Vigil season 3 sees Amy and Kirsten investigating the death of member of a covert British special forces mission, at a remote Arctic research station on Svalbard.
The synopsis for the season says: "Amy and Kirsten will need to catch the killer and defuse a potential international confrontation, as different nations compete for control of the Arctic and its resources in the changing polar climate, with both their careers and relationship on the line. As the mission rapidly unfolds, Amy and Kirsten begin to question who they can trust."
Vigil season 3 will air on BBC One and BBC iPlayer on Sunday 30 August. Seasons 1 and 2 are available to stream now on BBC iPlayer.
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