Notice in the stairwell: who turned off the light?

On Monday morning, Enrique Bordón, doorman of a block on Marina Street, tapes a handwritten A4 sheet onto the main letterbox: «Would the neighbour who switched off the hallway light on Sunday night kindly explain themselves to the community.» The note says neither what explanation, nor to whom.

At noon, Carmina Rueda from 3B, retired from retail, goes down for milk and signs underneath in red pen: «It wasn't me, I left at seven and came back at nine. Witness: Antonio from 3A.» By five in the afternoon, Antonio from 3A has added: «Confirmed. I was with my grandson.»

By Wednesday, the sheet is full: fourteen neighbours have sworn where they were between nine and eleven, three have brought receipts, two have reported others, and the lawyer from 5C has written in the margin that he reserves the right to take legal action.

On Thursday, mid-afternoon, Enrique goes down to the lobby with a ladder and a screwdriver. The timer of the light had been broken for a month: the contactor itself was switching it off, every night, at exactly eight past ten.