This presentation describes an engaging and colorful demonstration that was inspired by the observation of a beard that was dyed orange. The compound 2-hydroxy-1, 4-napthoquinone is the chemical which gives Henna, a natural dye, its characteristic color. The compound is yellow under acidic conditions, but orange under basic conditions. The demonstration uses an invisible ink of a dilute basic solution to write a message on a filter paper. On spraying the developing solution of 2-hydroxy-1, 4-napthoquinone in ethanol, the message is highlighted in orange whilst the background appears yellow. On then spraying a dilute acidic solution to the paper, the message disappears. The demonstration can be quickly, easily and safely prepared for use in a classroom or laboratory. The presentation will describe how the demonstration can be used, not only to attract students' attention, but to make concrete the concepts of resonance stabilization, keto-enol tautomerization and relative acidities.