The Dark ending explained: The killer unmasked, and Monica's past comes back to haunt her

There’s much to admire about ITV thriller The Dark, which follows a police investigation into a string of murders and attempted murders that send shockwaves through a community in the Scottish Highlands – a setting as breathtaking as it is unforgiving.

A serial killer is targeting young men and leaving their bodies exposed to the elements, pale and pristine, as though they had only just entered the world.

“That makes it even more intriguing and weird. It’s really eerie and creepy, and you want to know more about it,” said Mark Rowley, who plays DC Connor Crawford.

Gilles Bannier’s direction sustains a creeping sense of dread while a long list of credible suspects has you questioning almost everyone.

As DI Monica Dolan’s investigation ramps up, suspicion shifts from episode to episode – and, as the finale approaches, from moment to moment – until only one figure remains.

So, who is the killer? And what drove them to commit such chilling crimes?

Read on for a full breakdown of The Dark’s ending.

The Dark ending explained: Who was the killer?

It was Kyle Ward, the headteacher of the local high school, who was finally unmasked – literally – as the man responsible for the murders of Jason Morgan and Rob Wright, as well as several attempted killings.

During his final confrontation with Monica at the home of social worker Michael Bach, whom he also attempted to murder alongside his own daughter, Tammy, Kyle laid bare the twisted philosophy that fuelled his reign of terror.

Following the death of his wife, Kyle claimed he had “truly looked within” himself and emerged “liberated”. His grief was, in his own words, an enlightening experience that allowed him to embrace his “true self”, all while hiding in plain sight as a devoted father and pillar of the community.

He would identify young men who had plenty of promise but, in his eyes, “a tragic lack of vision”, and give them the opportunity to “do better in the next life”.

How very noble.

Said young men also appeared incredibly vulnerable – shaped by unrest at home, from extended parental absences (demanding jobs) to permanent absences (death), or experiences in the care system – who he groomed using burner phones which were distributed by Jason’s brother Nicholl.

Despite insisting that he had acted of his own volition, he, too, had been manipulated by Kyle after his mum’s partner Barclay had essentially forced him out of his own home.

There was only enough love for one of the Morgan brothers and that honour was bestowed upon Jason.

But that loss was Kyle’s gain, with Nicholl acting as his boots on the ground, so to speak, feeding any information back to him.

Owen MacLennan, the son of Gloria, who owns the sawmill that employs much of the town, was also one of Kyle’s apprentices.

Then, when the headmaster deemed the time was right for his victims to shuffle off this mortal coil, he would poison them and watch as the life drained from their bodies, each possessing a black onyx stone which he claimed would grant them safe passage into the next life.

But of course, Kyle’s justification was nothing more than a myth he clung to in order to rationalise his dark desires.

For all of his claims, none of this was about helping those young men who had supposedly lost their way. No, far from caring for them, this was about revelling in the control he held over them, particularly in their final moments, when “a life and all its dreams, hopes, potential” faded away.

It was about regaining the sense of control he had lost when the death of his wife upended his own life, leaving him staring into the abyss.

This wasn’t about mercy. It was about power and rage – which Kyle had twisted into a pseudo-spiritual rationale for cold-blooded murder.

But eventually, Kyle was undone by his own arrogance, courtesy of some very quick thinking by Monica, which resulted in him consuming the poison he had set aside for her.

Yet, despite the detective’s lucky escape, there was a storm brewing…

What Monica’s past means for The Dark’s future

In the closing moments of the finale, Monica opened a card addressed to her young daughter, Lucy. On the face of it, it’s a sweet, entirely innocent gesture.

But as we now know, Lucy’s father is the leader of the Burning Light cult, and Monica had spent years disentangling herself from the life she left behind.

But it seems her past has come back to haunt her once more.

“My darling daughter, it is time to let the light in,” it read, a message which understandably sets her teeth on edge.

“It is really fascinating,” said Donnelly of Monica’s history with the cult. “It was one of the elements that I really enjoyed digging into, regardless of what this first season covers.

“We don’t get the full story… and what I hope gets revealed over time, if we get to come back and do another season, is that there’s far more to explore there. There is this past, and it explains so much about her.”

Yet Monica’s life did not begin when she joined a cult.

“There’s also so much about her and her story with her father and her own history that came before that that explains how she also ended up in that situation,” added Donnelly.

“So there are lots of different threads that work together that are very layered. It’s not just this kind of, ‘here’s one explanation that happened in her past that tells you who she is now’ – which is [the case] a lot of the time.”

Expanding on how she believes The Dark stands apart from other crime dramas, Donnelly continued: “I think particularly with detective characters, we present somebody who’s troubled and complex and very good at their job, and we want to look at this one event that took place as to why they became who they are.

“And with Monica, it did seem to be, even from the first script, to be rooted so much more in the reality of what it is to live a life, that there are lots of different things that all thread together and become a tapestry of who that person is.”

“This story to do with the cult,” she added, “is just one element of that for her, and we get to explore that somewhat in the first season, and yet there’s still so much more to explore as well.”

The Dark is available to stream now on ITVX

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