Amnesty International Portugal : Letter from a Prisoner

Find the hidden message.

Published On
May 07, 2012

Editor's Pick

To highlight the human rights violations that take place in prisons, Amnesty International Portugal used text written in real lemon juice in a direct mail campaign - a method prisoners sometimes use to communicate with the outside world.

The mailing, by McCann Erickson Lisbon, arrived as an apparently blank sheet of paper but with a message to iron the paper. The hidden message revealed a letter highlighting the problems and directing readers to the Amnesty website. The agency says donations have increased by 35% following the campaign.