Sleuthic

The Black Files · October 12, 2026 · Difficulty: Detective

Black File #123 — SolutionFinal Rounds

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The case

Frances Delgado, regular, was found dead at Ironworks Gym at 10:45 PM. Seven people were at the scene. Exactly one of them was alone with Frances in the same zone.

The evidence (10 clues)
  1. Graham was standing on stairs.
  2. Carl was sitting in a chair.
  3. Graham was farther north than Audrey.
  4. Bridget was farther west than Audrey.
  5. Diane was farther north than Bridget.
  6. Erica was farther north than Bridget.
  7. Bridget was farther north than Graham.
  8. Carl was farther west than Diane.
  9. Diane was farther west than Bridget.
  10. Graham was farther west than Carl.

The answer

The killer: Audrey Quinn, alone with Frances Delgado in the Weight Floor.

Fixing rows and columns from the extreme-position clues cascades through the board and leaves Audrey alone with Frances in the Weight Floor.

Step-by-step deduction

  1. Before placing anyone, each clue eliminates cells:
  2. • Audrey: Graham was farther north than Audrey, and Graham is at least at row 5; Bridget was farther west than Audrey, and Bridget is at least at column F; column D belongs to Carl; column E belongs to Diane. Only G6 is left.
  3. • Bridget: was farther west than Audrey, and Audrey is no farther than column G; Diane was farther north than Bridget, and Diane is at least at row 1; was farther north than Graham, and Graham is no farther than row 6; Diane was farther west than Bridget, and Diane is at least at column D; row 5 already belongs to Graham; row 4 belongs to Carl; column E belongs to Diane; row 2 belongs to Erica. Only F3 is left.
  4. • Carl: was sitting in a chair; Graham was farther west than Carl, and Graham is at least at column B; was farther west than Diane, and Diane is no farther than column E; row 5 already belongs to Graham. Only D4 is left.
  5. • Diane: was farther north than Bridget, and Bridget is no farther than row 3; Carl was farther west than Diane, and Carl is at least at column C; was farther west than Bridget, and Bridget is no farther than column F; row 4 belongs to Carl; column D belongs to Carl. Only E1 is left.
  6. • Erica: was farther north than Bridget, and Bridget is no farther than row 3; column B already belongs to Graham; row 4 belongs to Carl; column D belongs to Carl; column E belongs to Diane; column G already belongs to Audrey; row 1 already belongs to Diane; column F belongs to Bridget. Only C2 is left.
  7. • Frances: Frances cannot be in the Parking Lot: the crime zone holds exactly two people and Carl and Graham are already there, and with Frances that would be more than two; row 5 already belongs to Graham; column B already belongs to Graham; row 4 belongs to Carl; column D belongs to Carl; column E belongs to Diane; row 6 already belongs to Audrey; column G already belongs to Audrey; row 1 already belongs to Diane; column F belongs to Bridget; row 2 belongs to Erica; column C belongs to Erica. Only A7 is left.
  8. • Graham: was on the stairs; was farther north than Audrey, and Audrey is no farther than row 7; Bridget was farther north than Graham, and Bridget is at least at row 2; was farther west than Carl, and Carl is no farther than column D. Only B5 is left.
  9. That already places Graham at B5, Audrey at G6, Carl at D4, Diane at E1, Bridget at F3, Erica at C2 and Frances at A7.
  10. With all seven placed, the only people in the Weight Floor are Frances and Audrey: Audrey was alone with the victim.
Solved map of Black File #123: Audrey G6, Bridget F3, Carl D4, Diane E1, Erica C2, Frances A7, Graham B5
The solved map: Audrey G6, Bridget F3, Carl D4, Diane E1, Erica C2, Frances A7, Graham B5.

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