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.
Case Unsolved
Dying Man's Letter
Completionist
Truth Revealed
Guest's Lost Cap
Bloody Knife
Missing Journalist
All Letters Found
All Keys Found
Charles Roberts' Story
Best Friends Forever
All Tools Found
Oliver Gibson's Story
Sofia Miller's Story
Dorothy Patterson's Story
All Newspaper Articles Found
Vivian Roberts' Story
Wanda Tyler's Story
Here Lies Sofia
Bernard Hopkin's Story
Steve Moss' Story
Scott Brooks' Story
Scott's Secrets
Derrick Tyler's Story
Trisha Roberts' Story
The Hidden Truth
The Secret Lies With Her
Matthew Brooks' Story
Mary Martinez's Story
Andrew Reed's Story
Tutorial Completed
James Howard's Story
You're Fired