The Silent Partner — hints

switch. That is the whole of it. It puts you in the other body — different room, different pockets, different everything — and switching back puts the first one exactly where you left them. status tells you who you are, where the other one is, the alarm and the clock.

That the two of you know different things. Take Ash up to the service riser off the second floor, and read the fire doors in the stair. Then switch and look at the building through Nadia's feeds. Then radio, because Nadia does not know about the riser until somebody tells her.

It is not. The building is empty, the badge is genuine, and the alarm does not move. Act I exists so that "which of us can do this" is automatic before it costs anything.

On a fixed round, the same round every night, and the only way to know is to be Nadia and look: feed desk, feed lobby, feed atrium. The moment you switch back to Ash that picture starts going out of date, and the Cameras meter is how out of date.

Yes. Being Ash means seeing four feet. Check the feeds, note where he is going to be, then move — and remember that every turn you spend being Nadia is a turn the round advances.

You can, and every release is a line in a log with Nadia's credential on it, and a door that opens for two minutes with nobody going through it is a shape a system knows. Use the riser: it is not on the system at all, because a riser is a hole and nobody puts a hole on a door schedule.

It is a maglock. There is nothing on Ash's side of it for anybody to do anything to. It opens from the system in the van, and the van is four hundred yards away and cannot walk through it.

She has never been told it exists. Examine the door as Ash, then radio, then switch.

That is the puzzle and that is the answer: unlock bay4 in 3. Queue the release for three minutes' time, switch, walk to the door, and be standing at it when it goes. The clock does not stop while you are switching, which is what makes it a two-person problem.

The comms room, which is where the access control box lives, and the plant room, where the fire stop round the riser has been cut and re-applied more than once by somebody who is not you.

The index for accession 4/11/07, in the cabinet marked 2007–2011 in the records office. Ash has a bar and a bar opens a filing cabinet in about four seconds.

radio. The act does not end until both of you know what it is a list of, because the whole design is that one of you knowing something is not the same as it being known.

He asked for the index. He did not ask about the box. There is exactly one thing you need a list like that for and it is not reading them.

Four clean rungs on the ladder, a fire stop cut and put back, a plant log initialled every week by somebody not on the maintenance contract, a four-inch gap on a shelf — and a flip chart in the meeting room, four pages back. Read it.

unlock the fire door as Nadia — ninety seconds of her credential, and he walks and she does not. walk out the front as Ash — four cameras, and he does not walk and she is never named. upload it as Nadia — ninety seconds, both of you go down, and it becomes an exhibit and can never be destroyed. Or leave it, and nobody is caught and nothing is saved.

No, and trying is worth doing once. Ash cannot upload from the fourth floor and Nadia cannot walk out of a building she is not in, and that constraint is the whole game restated at the end of it.

The game does not think one of them is. The endings are written to make that honest rather than coy.