"What!?" she says, looking rattled.

"Don't shit yourself," I say. "You're out of toilet paper."

Method

Okay, it's just a thumb-writer.

But in a way this is the perfect use for that tool. I'll explain in a second.

This idea is based on an email that Noel Qualter sent me:

The effect is you go to a friend's house and a few days later said friend is in the bathroom. They go to pull off the last piece of toilet paper and written on the tube is a message - ‘Hi Sharon, I reckon it’s 12.22pm on Wednesday 3rd. All the best."

All methods rely on you waiting till there’s only a few sheets left and guessing but that’s terrible.

I thought that was a great trick, but I knew there was no real, workable method to it. You can't force people to shit/piss and wipe themselves on a set schedule with a set number of pieces of toilet paper. So your prediction has to be done after the fact. Which means it can't be done without you there.

But I thought I could do something less perfect, but similar, and I dropped off three rolls of toilet paper with three friends so I could try it out.

I dropped those rolls off on August 19th, with only a vague idea of how I was going to finish the trick. If the idea didn't crystalize in a few days, there would be no trick. I would have just gifted some friends toilet paper for no reason.

My original method was to have the time the roll was finished written backwards on a thumbtip in dry-erase marker. And I thought I'd be able to just handle the roll briefly and stamp the time on the inside. This came nowhere near working.

Then I thought I needed something more like an actual stamp. So I spent hours and hours working on turning a thumbtip into something you could use to stamp the time on the inside of a TP roll. It involved little numbers that I formed out of rolled clay, which were then adhered to the thumbtip (barely). It was a huge waste of time. I spent days on this, trying to create this thumbtip stamp thing. And I got a super delicate version of something working right before my friend Chris contacted me to tell me he had finished his roll.

Before I go over his place I create the thumbtip stamp to match the time he contacted me. I have a little ink pad in my pocket so I can ink it up right before it's needed. It's kind of an awkward mess. But I go over to his place, just briefly handle the tube while I'm taking it off the holder, stamp in the time, and hand it to my friend. He tears open the tube and is momentarily flummoxed but then says, "Was this stamped?" While the numbers of the stamp were "hand-made" and imperfect, they didn't look like they were drawn with marker. They looked stamped. And then he kind of unravelled the whole method, realizing I must have stamped it in quickly post facto. Then he said, "If it had been written in there, I would have lost my shit."

Then it hit me: what am I thinking? We already have a tool to write with that attaches to the thumb. Why was I avoiding it in hopes of something more clever? This trick is actually perfect to use with a thumb-writer.

Your thumb is completely covered from all angles.

Messy writing is 10,000% justified. Writing with a full-size pencil on the inside of small tube would be messy.

Unless your spectator specifically knows about thumb-writers, there's no possible explanation for how the writing could have got inside there in the brief moment you held the roll. What I mean is, if you're using a thumb-writer with a post-it pad, it's possible they could hit on the idea that maybe you wrote your prediction later than they thought with a small pencil. But even with a tiny piece of lead it would be so awkward to put two fingers inside the tube to hold it and write something. It would be way too obvious.

So here's the choreography. I'm pretty happy with it.

1. I have a Sharpie in my shirt pocket and my thumb-writer is in the watch pocket of my jeans. And in my head I have the exact time I got their text (or phone call).

2. With otherwise empty hands, I hand the Sharpie to the person to sign the TP roll.

- Why do this? Because the only explanation will be that I somehow switched the roll. And the only way around that explanation is to make it unswitchable (have it signed), or to draw extra close attention to the roll during the whole procedure, which is not something I want to do when I'm going to be thumb-writing in it.

Plus, when the writing implement in play is a Sharpie, and the prediction is in pencil, I think that subtly suggests the prediction was not done just recently.

3. While she does this, I slip on the thumb-writer.

4. I have her remove the roll from the holder and I take it as if I'm going to tear it. Notice my thumb (and the secret writer) are naturally hidden in the tube exactly as it would be if I was doing this action for real.