BBC thriller Vigil has changed a lot over the years, and as it now approaches its third season, it has once again swapped out the majority of its cast and changed up its location and story.
However, one thing which has remained constant throughout is the central duo of Amy and Kirsten, played by Suranne Jones and Rose Leslie.
After Kirsten was expecting their baby in season 2, season 3 will find her hoping to go back to work, and finding the perfect opportunity when she is assigned to investigate a death on the Norwegian Arctic archipelago, Svalbard.
Unlike in previous seasons, this time Kirsten is the one to travel abroad and be on the ground, while Amy is assisting in the investigation from their home in Scotland. Now, creator and writer Tom Edge has explained how this shakes up their dynamic, and asks surprising and difficult questions for the couple.
"It feels like they have been on a very substantial journey together through the first two seasons, but those two seasons had been governed by a central dynamic, which was Amy in the thick of it, and very much the person who not just has seniority, but is entrusted with being the person who goes to the space where they are without supports and so on," Edge told Radio Times.
"And I think there's a world in which that dynamic could have continued, but things in their personal life have changed."
He continued: "For one thing, they have had a child together by the time we meet them, and Kirsten, after a combination of recuperation from injuries at the end of season two, and then also maternity leave, is at an interesting point in her career in terms of wishing to return to work, but perhaps needing to re-establish what the meaning of work is to her. And that cuts both ways in a relationship."
Edge added: "I think that would be familiar to many couples who have navigated shifts in priority and also shifts in the weighting of whose career comes first and how the world of family and multiple responsibilities begin to impact you there. So when we join them, they are at this talking point where it could be a return to business as usual.
"But, because of the nature of the case, it's decided that Kirsten should be the one to take off to Svalbard and lead on that. And even though that is a decision made from pragmatism about the investigation, it inverts things for them as a couple. It means that Amy's now the one trying to offer guidance and support from afar.
"And Kirsten has her own ambitions and desire to prove that she is every bit equal, if not in rank, then in capability. But she carries a certain amount of internal pressure into that, and I think we use that working dynamic to gently explore how some of the things in their relationship that have gone unspoken or untested are brought out into the open.
"And there are questions for Amy that have to do with control. I don’t mean that in a coercive sense, but a belief in herself that is challenging to extend to others. It's very much bound up in how she thinks about herself. So mixing things up in that regard allows us to open those relationship questions."
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The only other stars returning from previous seasons of Vigil for season 3 are Gary Lewis as DS Robertson and Dominic Mafham as Sir Ian Dowing, while new cast members include Jeppe Beck Laursen, Steven Miller, Naomi Yang, Benjamin Wainwright, Tornike Gogrichiani, Amy Manson, Steven Cree and Derek Riddell.
The synopsis for season 3 says: "DCI Amy Silva (Jones) and DI Kirsten Longacre (Leslie) return for a new case that takes them to a remote Arctic research station, where a member of a covert British special forces mission has been shot dead.
"Amy and Kirsten will need to catch the killer and defuse a potential international confrontation, driven by a land-grab for energy and resources in the changing polar climate, with both their careers and relationship on the line."
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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