Clues & Culprits › Archive › Oct 10, 2026 Hard walkthrough
Oct 10, 2026 Full Proof Walkthrough
Every verdict in the Hard case “The Waterfall on Mars”, in an order where each step is proven by the statements already on file.
Play it first Just a hint, please
This Hard case seats 20 suspects on a 4×5 grid. 18 of them carry a clue; the other 2 only have something to say about themselves. 6 of the steps can only be proven by reading two or more clues together. The order below is one valid route; any order where each verdict is proven when you enter it reaches the same answer.
Spoiler: show the full walkthrough
Start: Nora (B4) begins the case proven a criminal.
None of the cafeteria cooks is a criminal.— Nora, security chief (B4)
Step 1: Gus (C2, cafeteria cook) is innocent. This follows from Nora’s statement and the verdicts already proven.
Step 2: Hana (D2, cafeteria cook) is innocent. This follows from Nora’s statement and the verdicts already proven.
Step 3: Queenie (A5, cafeteria cook) is innocent. This follows from Nora’s statement and the verdicts already proven.
Step 4: Juno (B3, intern) is innocent. This needs 3 statements together — Gus’s, Hana’s and Queenie’s. Assume the opposite verdict and at least one of them breaks.
Exactly five of my eight neighbors are innocent.— Gus, cafeteria cook (C2)
An even number of my neighbors are criminals.— Hana, cafeteria cook (D2)
There is exactly one criminal above Juno.— Queenie, cafeteria cook (A5)
Step 5: Ruby (B5, security chief) is innocent. This needs 2 statements together — Queenie’s and Juno’s. Assume the opposite verdict and at least one of them breaks.
There are exactly three innocents in my column.— Juno, intern (B3)
Step 6: Dexter (D1, billionaire backer) is a criminal. This needs 2 statements together — Queenie’s and Ruby’s. Assume the opposite verdict and at least one of them breaks.
Celia and Gus have exactly two criminal neighbors in common.— Ruby, security chief (B5)
Step 7: Kira (C3, press photographer) is innocent. This follows from Dexter’s statement and the verdicts already proven.
If I'm a criminal, then Kira is innocent.— Dexter, billionaire backer (D1)
Step 8: Olive (C4, billionaire backer) is innocent. This needs 2 statements together — Hana’s and Kira’s. Assume the opposite verdict and at least one of them breaks.
Exactly two of the four billionaire backers are criminals.— Kira, press photographer (C3)
Step 9: Frank (B2, security chief) is innocent. This follows from Olive’s statement and the verdicts already proven.
If Frank is a criminal, then so am I.— Olive, billionaire backer (C4)
Step 10: Basil (B1, mission director) is a criminal. This follows from Queenie’s statement and the verdicts already proven.
Step 11: Iris (A3, press photographer) is innocent. This needs 2 statements together — Frank’s and Basil’s. Assume the opposite verdict and at least one of them breaks.
Exactly two of my eight neighbors are criminals.— Frank, security chief (B2)
Exactly one of my five neighbors is a criminal.— Basil, mission director (B1)
Step 12: Arlo (A1, intern) is innocent. This needs 2 statements together — Frank’s and Iris’s. Assume the opposite verdict and at least one of them breaks.
If Arlo is a criminal, then so is Emil.— Iris, press photographer (A3)
Step 13: Emil (A2, mission director) is innocent. This follows from Arlo’s statement and the verdicts already proven.
Exactly two of my three neighbors are innocent.— Arlo, intern (A1)
Step 14: Celia (C1, billionaire backer) is a criminal. This follows from Frank’s statement and the verdicts already proven.
Step 15: Lionel (D3, billionaire backer) is innocent. This follows from Gus’s statement and the verdicts already proven.
Step 16: Mila (A4, press photographer) is a criminal. This follows from Emil’s statement and the verdicts already proven.
There is exactly one criminal below me.— Emil, mission director (A2)
Step 17: Petra (D4, intern) is a criminal. This follows from Lionel’s statement and the verdicts already proven.
Exactly one of my five neighbors is a criminal.— Lionel, billionaire backer (D3)
Step 18: Suki (C5, mission director) is a criminal. This follows from Mila’s statement and the verdicts already proven.
Exactly two of Tess's three neighbors are criminals.— Mila, press photographer (A4)
Step 19: Tess (D5, intern) is innocent. This follows from Petra’s statement and the verdicts already proven.
An even number of my neighbors are innocent.— Petra, intern (D4)
The final lineup
| A | B | C | D | |
|---|---|---|---|---|
| 1 | Arlo innocent | Basil criminal | Celia criminal | Dexter criminal |
| 2 | Emil innocent | Frank innocent | Gus innocent | Hana innocent |
| 3 | Iris innocent | Juno innocent | Kira innocent | Lionel innocent |
| 4 | Mila criminal | Nora criminal | Olive innocent | Petra criminal |
| 5 | Queenie innocent | Ruby innocent | Suki criminal | Tess innocent |
What happened
Ares stopped working on its fourth day on Mars. Basil and Suki, the mission directors, hid the failure from the board, and Celia and Dexter, the two backers with the most to lose, decided the rover would keep exploring anyway. Mila shot the 'Martian' photographs in an Icelandic quarry through red filters; Petra, an intern who believed every spy novel she had ever read, smuggled the files onto the mission servers disguised as telemetry; and Nora, the security chief, made sure nobody traced where they came from. The hiker had posted the same waterfall on her holiday blog in 2019.