Sleuthic

The Black Files · October 13, 2026 · Difficulty: Detective

Black File #124 — SolutionWeight of Proof

Missed the case? Play Black File #124 →

The case

Fabian Okafor, supplement vendor, was found dead at Ironworks Gym at 6:05 AM. Seven people were at the scene. Exactly one of them was alone with Fabian in the same zone.

The evidence (10 clues)
  1. Gary was sitting on a sofa.
  2. Edith was the northernmost person at the scene.
  3. David was farther west than Bonnie.
  4. Edith was farther west than Amber.
  5. Amber was farther west than Gary.
  6. Bonnie was farther north than Amber.
  7. Clifford was farther west than David.
  8. Gary was farther north than Clifford.
  9. Edith was farther west than Clifford.
  10. Clifford was farther north than Bonnie.

The answer

The killer: Edith Sullivan, alone with Fabian Okafor in the Locker Room.

Fixing rows and columns from the extreme-position clues cascades through the board and leaves Edith alone with Fabian in the Locker Room.

Step-by-step deduction

  1. Before placing anyone, each clue eliminates cells:
  2. • Amber: Edith was farther west than Amber, and Edith is at least at column B; was farther west than Gary, and Gary is no farther than column G; Bonnie was farther north than Amber, and Bonnie is at least at row 5; row 6 belongs to Bonnie; nobody else can occupy column F, so it must be Amber. Only F7 is left.
  3. • Bonnie: David was farther west than Bonnie, and David is at least at column D; was farther north than Amber, and Amber is no farther than row 7; Clifford was farther north than Bonnie, and Clifford is at least at row 5; column G belongs to Gary. Only E6 is left.
  4. • Clifford: was farther west than David, and David is no farther than column D; Gary was farther north than Clifford, and Gary is at least at row 3; Edith was farther west than Clifford, and Edith is at least at column B; was farther north than Bonnie, and Bonnie is no farther than row 6. Only C5 is left.
  5. • David: was farther west than Bonnie, and Bonnie is no farther than column E; Clifford was farther west than David, and Clifford is at least at column C; row 1 belongs to Edith; row 3 already belongs to Gary; row 6 belongs to Bonnie; row 5 belongs to Clifford. Only D2 is left.
  6. • Edith: was the northernmost person of all, and since there is one person per row somebody occupies row 1: that is Edith; was farther west than Amber, and Amber is no farther than column G; was farther west than Clifford, and Clifford is no farther than column D; nobody else can occupy column B, so it must be Edith. Only B1 is left.
  7. • Fabian: row 1 belongs to Edith; column G belongs to Gary; nobody else can occupy column A, so it must be Fabian; row 3 already belongs to Gary; row 6 belongs to Bonnie; row 5 belongs to Clifford; Fabian cannot be in the Weight Floor: the crime zone holds exactly two people and Amber and Clifford are already there, and with Fabian that would be more than two; row 2 already belongs to David. Only A4 is left.
  8. • Gary: was sitting on the sofa; Amber was farther west than Gary, and Amber is at least at column C; was farther north than Clifford, and Clifford is no farther than row 5. Only G3 is left.
  9. That already places Gary at G3, Amber at F7, Bonnie at E6, Clifford at C5, David at D2, Edith at B1 and Fabian at A4.
  10. With all seven placed, the only people in the Locker Room are Fabian and Edith: Edith was alone with the victim.
Solved map of Black File #124: Amber F7, Bonnie E6, Clifford C5, David D2, Edith B1, Fabian A4, Gary G3
The solved map: Amber F7, Bonnie E6, Clifford C5, David D2, Edith B1, Fabian A4, Gary G3.

Play today's case →