Derren Brown’s latest stunt (where he ‘predicted’ the lottery numbers) has been the cause of masses of discussions at work about how he did it. There are plenty of theories about how he did it – so here’s my analysis.

First of all, what do we know?

  1. He turned around a plastic podium containing 6 balls which appeared to show the numbers drawn for Wednesday’s lottery.
  2. Nothing that he said or showed during the program was necessarily true.
  3. Nobody knew what Derren’s ‘prediction’ was in advance – his ‘prediction’ was only revealed once the answer was already known.

Actually that’s about all we can say for sure.

However, to this we can add some reasonable assumptions:

  1. The BBC draw is broadcast live.
  2. Time travel is not possible.
  3. The machine (if not tampered with), does not have a systematic flaw – and it is

    therefore impossible to predict any given draw based on past performance.

  4. It is impossible for him to have filmed every possible outcome in advance.
  5. He was always going to get the 6 balls right, so the rest was showmanship.
  6. … so there was no element of chance or luck.
  7. The machine cannot be influenced by ‘physic power’

So, as he said on Friday, there are three sensible options for how it was done.

  1. The numbers on the balls were only set once the numbers had been drawn (what he called “fixing the ticket”).
  2. The numbers were genuinely predicted in advance.
  3. The machine was fixed.

While he was very quick to discount number 1, it is the most likely by a country mile. Given the assumptions above, we can immediately reject (2). The probability of him getting even 5 balls right by chance is infinitesimal. While I haven’t looked up the coin tossing ‘experiment’, conditional probability is a bizarre and counter-intuitive creature (best displayed by that game where you have to choose the door that the prize is behind). However, the lottery isn’t conditional – what has gone before has no bearing on what happens next. I am disinclined to go with the third – but I wouldn’t discount it altogether, and it would also explain his reticence to showing his ‘prediction’ in advance… A lot of questions would be asked…

The really big question is why doesn’t he shows us his prediction in advance? It’s a thousand-fold superior trick if he shows us the numbers before (or even as) they’re drawn. As it stands he doesn’t actually predict anything – as I explained above. There are two reasons I can think of:

  1. He doesn’t know the numbers (“fake the ticket”)
  2. He does know the numbers (“fix the machine”)

Either way, there is no ‘prediction’ – the question is simply then how did he do it?

The whole “wisdom of crowds” thing is a nonsense in this context, and the group of 24 is a red herring. Notice on the Wednesday night they don’t get to know the prediction – he gathers in all the numbers, and works it out for himself. My theory is that the guy on the second draw who adds them up is a plant, and the lottery show is being showed with a delay. Either that or the whole thing is faked with 24 actors, but that feels like a bit of a cheat too far for me.

Secondly, the set up with the studio is just that – a setup. I believe that everything up to the cut away to the back camera has been pre-recorded, and we only become live once we cut back to what is almost certainly a camera on a tripod (either computer controlled, or with software shake).

That said, I believe Derren Brown was broadcasting live from a studio, with a TV showing the BBC, and he then walked over and turned around a podium that had six balls with the six lottery numbers actually written on them.

I believe there was either a second studio with an identical set-up and synced tripod movement, or a pre-recorded sequence of the exact same movement. A split screen from the live podium to the pre-recorded one was brought in, the balls were written on with the correct numbers, the dude doing the writing ran out, and the split screen returned to live.

This is exactly the trick used in 1,001 spy films (and Speed) where they pre-record footage, and replace the live feed with that pre-recorded footage. Heck, I’ve even done something similar with my noddy vision mixer. The two twists here are that only half the screen is replaced, and that there is a small amount of motion.

The best evidence for this theory is the well documented “jumping ball”. The leftmost ball (rightmost after they’re turned around) moves up a small amount between the last ball being drawn and Derren Brown walking back behind the podium. Clearly time was extremely tight – which might explain the ‘mistake’. The second piece of evidence was the unnatural movement of the camera – suggesting a tripod mount being moved by a servo.