A magic festival poster that reveals hidden copy only when photographed with a phone flash.

Québec City Magic Festival: The Magic Poster

To promote the Québec City Magic Festival, lg2 makes the poster behave like a trick, not a billboard.

The creative is a magician’s hat poster with a message printed in invisible ink. Curious passers-by discover the mechanic by doing what people already do. They pull out a phone, take a picture, and turn the flash on. The flash reveals the hidden copy, and a lucky few are rewarded with a free ticket for the festival’s closing show.

A poster that turns curiosity into participation

The mechanism is invisible ink plus a flash-triggered reveal. Instead of asking for attention, the poster pays attention back. It gives you a reason to stop, and it gives you a satisfying “aha” the moment you do.

In out-of-home, the strongest interactive ideas do not demand a new behavior. They attach to a behavior already in the environment and simply add a twist.

Why it lands for a magic festival

The medium is perfectly aligned with the message. The campaign does not merely advertise magic. It performs magic in the street. That alignment makes the experience feel like a preview of the festival rather than an ad for it.

Extractable takeaway: When promoting an experience product, make the marketing behave like the product. Let the audience sample the feeling, not just read the promise.

The free-ticket twist strengthens the loop. The reveal provides instant reward. The prize provides delayed reward. Both motivate sharing, because people want friends to try it and to see if they win.

What to steal for your next OOH execution

  • Hide something worth revealing. The reveal must feel like a payoff, not a gimmick.
  • Use a native trigger. Flash photography is a default phone capability, not an app install.
  • Reward the behavior. Even a small chance of winning can meaningfully increase participation.
  • Make it repeatable. The interaction should be easy enough that people can show someone else on the spot.

A few fast answers before you act

What is “The Magic Poster” concept?

A festival poster printed with invisible ink that reveals its message when someone photographs it with a phone flash, turning a passive billboard into a small magic trick.

Why is the flash-triggered reveal effective?

It uses a built-in phone behavior, creates instant payoff, and turns the audience into the operator of the trick, which increases attention and sharing.

What makes it more than a novelty poster?

The mechanic reinforces the product truth. The campaign demonstrates magic rather than merely claiming it, making the ad itself a preview of the festival experience.

How can brands adapt this without copying the exact technique?

Design a simple reveal that matches your story, attach it to a native behavior in the environment, and ensure the revealed content is genuinely rewarding, not just hidden for hiding’s sake.