Glass Room, The (Vera Stanhope #5) by Ann Cleeves; 2012/2018. Softcover.

DI Vera Stanhope is not one to make friends easily, but her hippy neighbours keep her well-supplied in homebrew and conversation so she has more tolerance for them than most. When one of them goes missing she feels duty-bound to find out what happened. But her path leads her to more than a missing friend. . .

It's an easy job to track the young woman down to the Writer's House, a country retreat where aspiring authors gather to workshop and work through their novels.

It gets complicated when a body is discovered and Vera's neighbour is found with a knife in her hand. Calling in the team, Vera knows that she should hand the case over to someone else. She's too close to the main suspect.

But the investigation is too tempting and she's never been one to follow the rules.