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# 3, 2, 1, blastoff

## The rocket-countdown, capture-the-evil-supervillain, card-prediction trick.

Here’s a James Bond-type card trick based around rocket launches, supervillains and secret codes. The scenario is the following: you write a prediction and put it to one side. Your spectator is now going to play the part of a rocket launch controller. It will be a tense time: how many of the four rockets will they be able to successfully launch? Some will launch, others will fail on the launch pad, but what is the identity of the supervillain behind the sabotage?

## Countdown

You shuffle the pack, then deal the top card face up onto the table. This is your first launch pad. As the card hits the table you and your spectator start the countdown at '10'. Deal the next card face up on top of the first as you both count 'nine', then for the next card you count 'eight', and so on – you get the picture. As you count down you’re looking for a 'hit' to launch the rocket. Like a tense game of snap a 'hit' happens when you deal a card with the same value as the number you reached in the countdown. Suppose at the count of 'five' the card dealt is also a five. You have a hit, you have blastoff and the countdown halts. Success! Court cards – jacks, queens and kings – all count as 10 in this trick. If the countdown manages to get all the way to one without a hit (matching card and number) the rocket fizzles out on the launch pad, the villain has managed to sabotage the launch, and you deal an extra face-down card on top of it (card 'zero') to cover the launch pad.

## Failure to launch?

After you demonstrated the first launch or fizzle you can hand the deck to the spectator. Tell them to try and launch three more rockets using the same rules. After these attempts (and it’s lots of fun – will the rocket launch or fizzle?) you will have four piles of cards on the table. These piles will either have a face-up card (where the launch happened) or a face-down card (where the countdown fizzled out and the launch pad was capped).

## The secret code

The evil mastermind behind the sabotage has hidden their identity in a secret code (as megalomaniac masterminds do). Look at the values of the cards on the face-up piles. These are the secret code numbers that will reveal the evil villain behind the sabotage. Add these numbers together to find the total. Then ask the spectator to count that number of cards from the undealt portion of the deck. They turn the last card over, and zap! It’s the villain’s calling card you predicted at the start. Out-of-this-world magic, or is there a more down-to-earth explanation for your psychic ability?

## How on earth does it work?

It’s not magic, it’s maths.Be sure your deck has all 52 cards before you start, with no jokers. Before the trick starts make sure you know the value of the face-down card that is nine from the bottom of the deck. This is your prediction. You can shuffle the top cards so long as you pull from the middle of the deck, without disturbing the order of the bottom nine cards. So our known card, the 9th card from the bottom, will be at position 52-8 = 44 (remember there are 8 cards under the selected card and the bottom of the deck).

## If nothing launches

Suppose all the launches fizzled. In each pile you would have 10 cards plus one extra covering each pile so that 11 cards in the pile, times 4 piles = 44 cards. There would be no code number to use so the top card on the undealt pile would be the ‘villain’, and that would be the predicted card.

## When one rocket launches

What happens, maths-wise, when a rocket launches? Well, suppose the launch takes place at countdown number X. This means that on the pile that launched, there’s a card with value X showing and the undealt pile has 11-X more cards than the case where the pile hadn’t launched. If all the piles launched the undealt pile would contain 9 cards, the top card being the prediction. But when a pile launches you stop dealing cards into it, so the pile of undealt cards stays bigger. For example if the rocket launches when X=6, the undealt pile now contains 5 more cards that it would if the pile had fizzled, so it contains 14 cards. When doing the code count we now count down to the 6th card from the top of these 14. You count down through 14,13,12,11,10 and finally get to 9 the ninth card again, our prediction. This works for any X. The stop in the countdown leaves a card with the X value on show, giving the code to count down to the 9th card. The two factors, the card showing and extra number undealt, balance each other out. It’s just simple addition disguised.

## It just keeps going

With addition we can simply extend this to all four piles. Each pile that launches adds its secret code number and an identical number of undealt cards to balance out, ensuring that whatever happens the final count will always end at the predicted 9th card from the bottom.

## Variations

If you don’t fancy doing the false shuffle or having to set up the cards before, you could simply have the spectator shuffle the cards (to show all’s fair and above board). then deal out 8 cards. You could explain this as an example to explain the sort of thing you’re going to ask them to do, or to ‘show the cards are well shuffled’. What you’re really after, though, is a sneaky peak at the bottom card. After the demonstration, put the 8 cards on the bottom of the pack, so the card you glimpsed is now at the 9th, position ready for you to write your prediction and work your magic.

Now you know the workings of the trick you could add extra mystery to it. The court cards don’t need to have the value 10, so long as you keep the values consistent. For example a jack could equal 4, a queen 7 and a king 9 They can have any value between 1 and 10. The compensation maths works just as well, but perhaps the trick gets more complicated to explain.

Like all good magic an effect is a combination of the secret wrapped in a good presentation that’s easy to follow. Practice the mechanics of the trick, get creative and tell a good story. If you do your audience will believe you have powers literally out of this world.