Clues & Culprits › Archive › Oct 23, 2026 Medium walkthrough
Oct 23, 2026 Full Proof Walkthrough
Every verdict in the Medium case “912 Flights Without Leaving Home”, in an order where each step is proven by the statements already on file.
Play it first Just a hint, please
This Medium case seats 20 suspects on a 4×5 grid. 15 of them carry a clue; the other 5 only have something to say about themselves. 2 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: Greta (C2) begins the case proven a criminal.
My row has exactly three innocents.— Greta, pilot (C2)
Step 1: Emil (A2, pilot) is innocent. This follows from Greta’s statement and the verdicts already proven.
Step 2: Amir (A1, smuggler) is a criminal. This follows from Emil’s statement and the verdicts already proven.
The person above me is a criminal.— Emil, pilot (A2)
Step 3: Frank (B2, customs officer) is innocent. This follows from Greta’s statement and the verdicts already proven.
Step 4: Hugo (D2, smuggler) is innocent. This follows from Greta’s statement and the verdicts already proven.
Step 5: Joan (B3, air-traffic controller) is a criminal. This follows from Hugo’s statement and the verdicts already proven.
Exactly one of Joan and me is a criminal.— Hugo, smuggler (D2)
Step 6: Nora (B4, customs officer) is innocent. This follows from Frank’s statement and the verdicts already proven.
There is exactly one criminal below me.— Frank, customs officer (B2)
Step 7: Iris (A3, travel vlogger) is innocent. This follows from Nora’s statement and the verdicts already proven.
Iris and I are either both criminals or both innocent.— Nora, customs officer (B4)
Step 8: Mila (A4, travel vlogger) is a criminal. This follows from Iris’s statement and the verdicts already proven.
Exactly two of my five neighbors are criminals.— Iris, travel vlogger (A3)
Step 9: Kira (C3, travel vlogger) is innocent. This follows from Mila’s statement and the verdicts already proven.
Exactly one of Kira and me is a criminal.— Mila, travel vlogger (A4)
Step 10: Olive (C4, first-class passenger) is a criminal. This follows from Joan’s statement and the verdicts already proven.
Exactly three of my eight neighbors are criminals.— Joan, air-traffic controller (B3)
Step 11: Ruby (B5, customs officer) is innocent. This follows from Frank’s statement and the verdicts already proven.
Step 12: Suki (C5, pilot) is a criminal. This needs 2 statements together — Kira’s and Olive’s. Assume the opposite verdict and at least one of them breaks.
Exactly four of my eight neighbors are criminals.— Kira, travel vlogger (C3)
Exactly four of my eight neighbors are innocent.— Olive, first-class passenger (C4)
Step 13: Theo (D5, air-traffic controller) is a criminal. This needs 2 statements together — Kira’s and Olive’s. Assume the opposite verdict and at least one of them breaks.
Step 14: Celia (C1, first-class passenger) is innocent. This follows from Theo’s statement and the verdicts already proven.
Column C has exactly three criminals.— Theo, air-traffic controller (D5)
Step 15: Dexter (D1, first-class passenger) is innocent. This follows from Celia’s statement and the verdicts already proven.
All the criminals in my row are connected.— Celia, first-class passenger (C1)
Step 16: Bruno (B1, customs officer) is a criminal. This follows from Amir’s statement and the verdicts already proven.
There is an odd number of criminals to my right.— Amir, smuggler (A1)
Step 17: Lionel (D3, first-class passenger) is a criminal. This follows from Suki’s statement and the verdicts already proven.
There are exactly two innocents above Pia.— Suki, pilot (C5)
Step 18: Pia (D4, smuggler) is innocent. This follows from Kira’s statement and the verdicts already proven.
Step 19: Quinn (A5, air-traffic controller) is innocent. This follows from Ruby’s statement and the verdicts already proven.
My row has exactly two criminals.— Ruby, customs officer (B5)
The final lineup
| A | B | C | D | |
|---|---|---|---|---|
| 1 | Amir criminal | Bruno criminal | Celia innocent | Dexter innocent |
| 2 | Emil innocent | Frank innocent | Greta criminal | Hugo innocent |
| 3 | Iris innocent | Joan criminal | Kira innocent | Lionel criminal |
| 4 | Mila criminal | Nora innocent | Olive criminal | Pia innocent |
| 5 | Quinn innocent | Ruby innocent | Suki criminal | Theo criminal |
What happened
Lionel's boarding passes were real; his seats were empty. Joan and Theo, two air-traffic controllers, logged his flights as full; Greta and Suki, the pilots, added his name to their manifests whenever they flew; and Bruno, a customs officer, swiped him through a staff gate that recorded every 'departure'. Olive, a first-class regular, sold the free flights to her friends at half price; Amir, a smuggler with a talent for printing, made the matching luggage tags; and Mila filmed a travel vlog of 'Lionel's year in the sky' using stock footage. Lionel spent the year at home, gardening.