Titles:
The Dark Wives
The Darkest Evening
The Rising Tide

The Vera Stanhope Series Book 9-11 by Ann Cleeves 3 Books Collection Set (The Darkest Evening, The Rising Tide & The Dark Wives):

The Dark Wives:
When a body is found on the common outside Rosebank, an isolated care home for troubled teens, DI Vera Stanhope is called out to investigate. The victim is Josh, a staff member, who never showed up to work, and her only clue is the disappearance of fourteen-year-old resident Chloe. Vera can’t bring herself to believe that a teenager is responsible for the murder, but even she can’t dismiss the possibility.Then, in the isolated wilds of the Northumbrian countryside, near the Three Dark Wives standing stones which have triggered legends across the centuries, a second body is found.

The Darkest Evening:
The darkest nights can hide the deadliest secrets . . .Driving home during a swirling blizzard, Vera Stanhope’s only thought is to get there quickly.But with the snow driving down heavily, she becomes disorientated and loses her way, eventually stumbling on another car abandoned on the road. With the driver’s door open, Vera assumes the driver has sought shelter but is shocked to find a young toddler strapped in the back seat.

The Rising Tide:
Fifty years ago, a group of teenagers spent a weekend on Holy Island, forging a bond that has lasted a lifetime. Now, they still return every five years to celebrate their friendship, and remember the friend they lost to the rising waters of the causeway at the first reunion.Now, when one of them is found hanged, Vera is called in. Learning that the dead man had recently been fired after misconduct allegations.