Here is the full list of all 33 The Painscreek Killings achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Completionist
Truth Revealed
Case Unsolved
Mary Martinez's Story
Bloody Knife
Matthew Brooks' Story
All Letters Found
Charles Roberts' Story
Vivian Roberts' Story
Sofia Miller's Story
Missing Journalist
Best Friends Forever
All Keys Found
Steve Moss' Story
All Tools Found
Oliver Gibson's Story
Dorothy Patterson's Story
All Newspaper Articles Found
Bernard Hopkin's Story
Wanda Tyler's Story
Here Lies Sofia
Scott Brooks' Story
Scott's Secrets
The Hidden Truth
Derrick Tyler's Story
Trisha Roberts' Story
Andrew Reed's Story
The Secret Lies With Her
Guest's Lost Cap
Dying Man's Letter
Tutorial Completed
James Howard's Story
You're Fired