A Lie Detector Magic Trick Method

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There’s no doubt in my mind which effect I most recommend when consulting for famous magicians: it’s Odd Ball by Marc Oberon.

It’s hard to say what makes the marketed effect more compelling — it might be the fact that, as I writer, it’s easy to get excited about the many presentational uses for the prop.

Any routine you come up with will be engaging, as are all games. Plus, the prop provides an easy reason to bring multiple people onto stage in an easy-to-manage way.

It’s also at the far end of “proppy” without being too “proppy” — while many magicians these days, overly inspired by David Blaine, avoid using props at all costs — a black bag with five balls in it for a mentalism game just about feels okay.

Blaine uses props too sometimes, so it’s going to be okay.

Honestly, the main reason I recommend Odd Ball is probably because its method is so goddam devious. It’s the sort of secret you learn and instantly fall back into laughter.

We don’t get many new methods like those these days — in recent years, new methods have mostly come in the form of technological or manufacturing advances (an old trick suddenly enhanced by fancy new tech or breakthroughs in ways to build the same idea into smaller form-factors, with better strength or reliability — more on this later).

Odd Ball’s method is so simple and reliable it’s ridiculous.

You likely first saw it performed on stage by a famous UK mentalist.

Multiple spectators join you on stage and each reaches into a bag to retrieve one of a handful of balls while you look away.

Most of the balls are white.

One ball is black.

The performer knows who has the black ball immediately, but you can have some fun with it for ten minutes or so on stage. It is most commonly performed as a lie detector routine — in which the spectators answer questions and tell the truth or lie depending on which ball they chose, and the magician always knows who is lying.

Presentational Notes

Over the summer, I saw Nick Mohammed perform at the comedy festival in Montreal. Nick is well-known for his role as Nate in Ted Lasso, but he also has a comedy character called Mr Swallow who performs a range of impossible feats and magic tricks.

He’s a talented and very funny performer.

Nick performed a lie detector routine using five cards that were chosen (not balls) by audience members on stage. In his routine — one person was the liar and he had to figure out who was lying in response to his comedic questioning.

When I saw the show, the person who had to lie was a terrible liar.

They gave bizarre answers and giggled a lot.

I’m pretty sure one of the questions was “When did you last do a poo?” and the answer they gave was long enough ago that, if true, they ought to really be in the hospital.

Everyone in the audience instantly knew who the liar was long before Nick got around to guessing. I was struck by this, because it was my understanding that one liar and four truth tellers was the way most people perform this routine — there must be a way to mitigate the risk of randomly selecting a terrible liar.

It might make sense to have four liars and one truth teller.

To switch the format upside down — eliminate the liars, and find the truth teller instead.

It’s less likely that people are a bad truth tellers than bad liars.

So if four of the people are telling lies, it might be more compelling for the audience to see you eliminate those people one by one.

It’s definitely something to try and see how it feels. You’d probably still want to present it as a game of “finding and eliminating the liars” — because the focus on spotting liars is instinctively more enticing than finding a truth teller.

A Close-Up Version

I’ve long obsessed over ways to perform Odd Ball in a more organic close-up setting.

In my book, Only Ideas, I describe performing the same method but with a bag of candy gum balls instead.

In the special pre-order edition of my book, Magic for the Rest of Us, I describe a way to perform the effect with cards — the cheeky aspect to the method there was that in the first round of the routine all of the spectators actually have identical cards — so you can hand them out freely without looking, letting them pass the cards out between them themselves. In the first round, eliminate any three you wish, then “to make things more difficult,” take back the two final cards in play, mix them up (and secretly switch in a card with the other option on it), and then the two final spectators choose again (when there’s less heat on the section process).

Still, it’s unclear if cards are the right choice in a close-up setting with friends.

Coin Effect Idea

You borrow a selection of coins, such that four of the coins are one colour (or amount) and that one of the coins is a different colour (or amount). In the UK, that might be four silver ten pence coins and one gold pound coin.

You close your eyes and look away, as each friend takes one of the coins from a bowl or folded napkin. You do not see or peek who takes which coin.

Now, onto the game — the person who chose the gold coin is the truth teller.

Everyone else must answer with a lie to all of your questions.

You ask the friends individually simple questions like “What time did you fall asleep last night?” or “Do you have the gold coin in your hand?” (All of them will say yes to that second question).

You eliminate them one by one and always know which friend has the gold coin.

The Method

The idea for this trick relies on a prop many of the readers will own, but can easily be bought from any magic shop. You’ll need to test the method with your own props and find a handling that works best for you.

The coins can be placed in the open, like on the table itself, but it’s likely more compelling for all if the friends also do not know who has the truth teller coin — therefor, covering the coins with a napkin or placing them inside of a bowl is probably best.

To begin the trick, it’ll likely be best to simply take out a handful of coins, selecting two or three, and borrowing the rest from friends. Present it as though the group is working together to find the necessary coins — as you would before playing any coin game.