The scene
Cultural Centre · Model workshopThe model of the square is found with its fountain in a different position. The installation recording shows that one person completed the entire operation in the workshop during a precisely known interval.
Three assistants were in the foyer before and afterwards. No camera shows the corridor. The times on their photographs look close together, but come from two devices with different clock settings.
What we know for certain
One of these three people made the entire change without help. They had to be in the workshop from 16:05:00 to 16:06:30 in real time. There were no shortcuts or remote controls. The recorded periods of presence and clock offsets are exact.
The three accounts
Sira Peña
Model maker«I had a short break between my photographs.»
Tomás Roca
Coordinator«I returned to the foyer before the announcement.»
Uma Font
Lighting technician«I was also absent for a while.»
Examine the evidence
0 of 5 openedOpening these five clues does not cost points.
01The minimum journey
Going from the foyer to the workshop takes at least 30 seconds. Returning takes another 30. It is possible to wait inside, but those journey times cannot be shortened.
02The two devices
Camera A is two minutes fast. Camera B is one minute slow. Neither clock changed its offset during the test.
03Sira’s photographs
Sira remains visible in the foyer until 16:06:45 on A. She becomes visible again from 16:06:10 on B.
04Tomás’s photographs
Tomás remains visible until 16:06:20 on A. He becomes visible again from 16:06:10 on B.
05Uma’s photographs
Uma remains visible until 16:06:20 on A. She becomes visible again from 16:05:45 on B. Nobody is absent outside these gaps.