Everyone deserves a second chance, but how far would you go for one?

In Edinburgh, one man is about to find out. Garry Plumb has always been invisible – a solitary data analyst whose cruel past left him incapable of forming relationships.

But when a colleague's sister is murdered, Garry’s world cracks open. A chance encounter with the enigmatic Billy Blunt introduces him to a secret that defies reality: a living device capable of sending its holder back in time, offering the chance to rewrite the past and reshape the present.

As Garry steps into his own history, the chance to right old wrongs and erase the scars of trauma proves intoxicating. But with every change he makes, the line between justice and vengeance blurs.

Meanwhile, DCI John Waters is closing in on a chilling pattern of murders, unaware that the trail he's following is about to lead somewhere no investigation has gone before.

How can you save somebody else if you can't save yourself?

When widow and young mother Stephanie McKinnon's disappearance in the Scottish Borders is escalated to the Major Investigations Team, it couldn't have come at a worse time for DCI John Waters. Pulled into a complex case while dealing with his own torment, his inner demons threaten to consume him.

Garry Plumb, meanwhile, is building a life he never thought possible – a thriving company, a fiancée he adores, and a future that almost lets him forget what he is. But the beast inside hasn't gone anywhere. Its just waiting for a reason to come out – and it finds several.

Garry tells himself that each kill is righteous, but there's no escaping that the voice talking him into it doesn't sound like his conscience. This voice is familiar, and monstrous.

Waters' desperation to reunite the missing mother with her little boy grows and, knowing things nobody else does, he turns to Garry. The only question he needs to answer is: can Garry's past save their future, or has he become the very thing he once destroyed?

The enthralling trilogy reaches its devastating conclusion.

Garry Plumb has built the life he always dreamed of – a successful business, a loving wife, and a beautiful baby girl. But beneath the surface, he harbours a dark secret: a pact that allows him to hunt down and eliminate killers before they can strike.

When a sadistic predator with a monstrous purpose begins leaving bodies across Scandinavia and Scotland, DCI John Waters turns to Garry – the only weapon he has left.

 
As Garry’s past becomes inextricably entangled with this new foe, his perfect world begins to crumble. With his mind deteriorating and timelines fracturing, he must race against time to save those he loves – but every trip costs him more than he can afford to lose.

The final reset is coming, and there is no turning back.