Who was in the building on 12 November 1986

The staff photograph in the locker room is dated July 1985 and shows twenty-one people on the steps of the ground floor entrance. Four of the faces have been scored out with a ballpoint pen, hard enough to tear through the emulsion.

The duty roster for 12 November 1986 names four people. They are the same four.

Dr Miriam Vance — Director

Vance built the programme, wrote its protocol, and defended it to a licensing board four times. She is precise, warm, and entirely certain she is doing something good. She never raises her voice, on tape or on paper, and the effect over eight years of documents is not reassuring — it is the opposite.

Her office is on the first floor. In it are the transparencies she used for board presentations, an appointment diary, and a letter to the Board that she dictated on the afternoon of 13 November and never sent. The letter asks to extend the permitted observation period from eight hours to sixteen. It contains one sentence that her own dictation tape catches her refusing to soften.

Dr Theo Kessler — Staff physician

Kessler is anxious, formal in writing and blunt on tape. He filed six written objections to the length of the observation period. Five of them are not in the record, and he kept carbon copies of all six off site because he expected exactly that.

He was rostered to observation on the night of 12 November — a duty he had not performed in nine years — by the Director, who does not write the roster. He recorded a dictation the night before saying so, and saying that he was going to run the session anyway, and saying why.

Ruth Palliser — Night records clerk

Palliser worked records for nine years and counted sheets for a living. She is dry, funny and relentlessly observant, and she annotated everything in pencil, which is the reason a great deal of this story is recoverable at all. Her marginalia is the most reliable narrator in the building.

At one in the morning on 13 November she was told to close up and go home. She wrote in the official day book that she had been told and that she had not gone, and then she said the same thing into a tape recorder, because — in her words — "the book is a book and books get lost".

Alton Reeve — Night security officer

Reeve is bored, thorough and honest, and his camera logs are the only record in the building that nobody thought to edit. He wrote down what he saw, in order, with times, including the parts that make him look foolish.

At twenty past four on the morning of 13 November he recorded that the vestibule turnstile registered an entry with nobody in the picture, said on tape that he was going down to look, and went. The tape keeps running for three minutes and nine seconds after the door closes behind him.

Odile Aldaine — Subject 114

Not staff, and not on the roster, but in the building. Admitted on 18 September 1986 for chronic insomnia, aged 31. Heard only on tape: lucid, tired, funnier than her situation, and — across the surviving session recordings — increasingly and specifically aware that something about the order of her memory has stopped being reliable.

Her family were told she discharged herself in December. She did not come home.

What the four faces mean

Somebody went through this building after February 1987 and removed the same four people from every record they could reach. They got the payroll, most of the contracts and two pages of the visitor register. They did not get the night watch log, because it was in a locked cabinet in the security office and the key had been taken off hook 14 and never put back.

They did get the photograph. It took about four seconds with a biro and it is the only piece of the cover-up that was done by hand, in anger, by somebody who was looking at those four faces while they did it.

Every character, organisation, document and event described here is invented for this game.