The Lie Detector

Originally posted on September 1, 2018 by Damien

I’ve mentioned the first “real” magic trick that I learned was entitled Lie Detector, and it uses the Si Stebbins stack. I don’t even know if I still have the written instructions I bought back in the mid nineties, or if they’ve been turfed in one clean out or another. Fortunately I have this trick well and truly committed to memory, and I’ve not needed to refer to the instructions for quite a few years.

The Trick:

The way it works is you get a volunteer to cut the deck, then take a card from anywhere in the deck and show it to everyone else (assuming there are others watching, of course). You then tell them that you’re going to ask them 3 questions about their card, and that they can choose to answer truthfully, or lie.

The three questions are the colour, the suit, and the value of the card. For each question, you spell out the answer, dealing off a card for each letter, with one extra as you say the answer again. For the value, to add a bit of variety, you can ask if they would like it counted or spelled (assuming they didn’t name a face card). Each card is flipped in turn, and indicates the actual colour, suit and value of the chosen card.

How to do it:

Have the volunteer cut the deck and complete the cut. Then get them to select a card. However you do it, you need to be able to cut the deck at exactly the point where their cards is. Fanning out is good for this, as is riffling and getting them to say stop. While they are looking at the card, cut the deck where they their card was, and complete the cut. This should put the card underneath theirs on top of the deck.

Now comes time for the questions. The first question is easy: ask if the card is red or black. Spell out the answer, taking off a card for each letter (pro tip: keep the cards in the same order in your hand, rather than dealing them onto the table, it makes resetting the deck much easier later[1]). Set the cards used to spell the word down, then deal the next card separately as you repeat the answer.

The next question depends on the colour the volunteer gave. If they said black, you ask “Is your card a spade, or is it one of the clubs?” If they said red, then you ask “Is your card a diamond, or is it one of the hearts?” This wording is important, as you need to count off the right number of cards, and only using spade, clubs, diamond or hearts* will work for this. As with the colour, spell out the suit while dealing out cards, and place them beside the first packet, then say the suit again as you deal off one more card separately.

*One important note: If they say the suit is hearts, then you need to be sneaky as you count the cards off, and count an extra card. If you don’t do this, then the trick won’t work.

The final question is the value of the card. A nice touch is to ask if they want this counted out or spelled, as it truly doesn’t matter how many cards you deal out. Place the cards beside the second packet. Unlike before you won’t deal off an extra card. Instead, recap the trick so far, reminding them that they had a free choice of card, and could have chosen to tell the truth or lie when they answered your questions. While you do this, casually take the top card of the counted pile and place it separately.  You’re now ready to reveal the cards.

Starting with the colour card, remind them of their colour, and flip the card. If they told the truth, then the colour will be the same, if it’s not, then they lied. You can then flip the suit card. If they lied about the colour, then I like to say something along the lines of “Well, you said the card was [suit], but we know it can’t be that, because that’s the wrong colour, it’s actually [correct suit]”. Now that you know the colour and suit, the last card will be the same number as their card, and you should have an audience staring at you in amazement as you correctly name their card.

Of course, if you try and perform this trick without practising, like I did, then you’ll most likely end up with completely wrong cards, and a very red face. So, learn from my mistakes, practise until you can perform the trick in the dark with your hands behind your back before performing it for actual people. Well, okay, maybe that’s a bit over the top, but at least be confident you can get the trick right no matter what colour or suit they answer.

[1] I mentioned keeping the cards in order as you deal them out makes resetting the trick easier. Here’s how to quickly reset the deck for the next time:

1. Take the card that revealed the number, and place it on top of the cards counted out for the number. Place that packet on the top of the deck
2. Take the card that revealed the suit, and slide it underneath the cards you counted off spelling out the suit. Use it to pick them all up into a packet, and place it on top of the deck.
3. Repeat step 2 with the colour cards.
4. Finally, place the card the volunteer chose on top of the deck.  You’re now ready to perform again.