Sleuthic

The Black Files · October 4, 2026 · Difficulty: Investigator

Black File #115 — SolutionFinal Rounds

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The case

Grace Underwood, boxing coach, was found dead at Ironworks Gym at 12:50 AM. Seven people were at the scene. Exactly one of them was alone with Grace in the same zone.

The evidence (9 clues)
  1. Dominic was standing on the stairs.
  2. Ernest was in the Parking Lot.
  3. Bridget was sitting on the sofa.
  4. Claire was standing on the floor.
  5. Anthony was standing on the floor.
  6. Ernest was standing on the floor.
  7. Claire was the easternmost person at the scene.
  8. Claire and Faye were in the same zone.
  9. Anthony was the westernmost person at the scene.

The answer

The killer: Bridget Winters, alone with Grace Underwood in the Front Desk.

Fixing rows and columns from the extreme-position clues cascades through the board and leaves Bridget alone with Grace in the Front Desk.

Step-by-step deduction

  1. Before placing anyone, each clue eliminates cells:
  2. • Anthony: was standing on the floor; was the westernmost person of all, and since there is one person per column somebody occupies column A: that is Anthony; row 6 belongs to Bridget. Only A3 is left.
  3. • Bridget: was sitting on the sofa; column A belongs to Anthony; column G belongs to Claire; row 5 belongs to Ernest; column B belongs to Ernest; row 1 already belongs to Claire; only Grace and the killer were in the crime zone (the Front Desk) and only Bridget and Grace can be there; column E belongs to Grace. Only C6 is left.
  4. • Claire: was standing on the floor; was the easternmost person of all, and since there is one person per column somebody occupies column G: that is Claire; row 5 belongs to Ernest. Only G1 is left.
  5. • Dominic: was on the stairs; column A belongs to Anthony; column G belongs to Claire; row 5 belongs to Ernest; column B belongs to Ernest; nobody else can occupy row 2, so it must be Dominic. Only F2 is left.
  6. • Ernest: was in the Parking Lot; was standing on the floor; column A belongs to Anthony. Only B5 is left.
  7. • Faye: was in the same zone as Claire, and Claire can only be in the Locker Room; column G belongs to Claire; row 5 belongs to Ernest; column B belongs to Ernest; row 1 already belongs to Claire; nobody else can occupy row 4, so it must be Faye; nobody else can occupy column D, so it must be Faye. Only D4 is left.
  8. • Grace: Grace cannot be in the Parking Lot: the crime zone holds exactly two people and Anthony and Ernest are already there, and with Grace that would be more than two; column G belongs to Claire; row 5 belongs to Ernest; column B belongs to Ernest; nobody else can occupy row 7, so it must be Grace; column F already belongs to Dominic. Only E7 is left.
  9. That already places Claire at G1, Ernest at B5, Dominic at F2, Faye at D4, Anthony at A3, Bridget at C6 and Grace at E7.
  10. With all seven placed, the only people in the Front Desk are Grace and Bridget: Bridget was alone with the victim.
Solved map of Black File #115: Anthony A3, Bridget C6, Claire G1, Dominic F2, Ernest B5, Faye D4, Grace E7
The solved map: Anthony A3, Bridget C6, Claire G1, Dominic F2, Ernest B5, Faye D4, Grace E7.

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