Color Sight by Devin Knight
A spectator chooses one of 20 different colors. Then she can nominate another person to take part in this experiment.
Without a word, you first look the viewer in the eye, then the second person. After a few moments, ask that person if a color came to their mind, and surprisingly they say yes! answers - And what color did you think of? - To which she replies green!
The first viewer confirms that she actually chose green.
The experiment is immediately repeated. The spectator chooses a color again and this time no one else knows what color it is. - And again you look the second viewer in the eye and shortly afterwards ask him if he saw anything. Again, the spectator names a color that turns out to match the color chosen by the spectator! Namely blue.
With this effect you will amaze not only all viewers, but also colleagues with magical knowledge. The method is as simple as it is ingenious and inscrutable.
In the German-language instructions, the original version is also described in detail, as well as a comedy version as a bonus!