In 1953, magician John Mulholland quietly left his post editing the trade magazine The Sphinx to write two classified guides for the newly formed CIA: Some Operational Applications of the Art of Deception and Recognition Signals. Commissioned during the MKUltra years, they covered things like palming a pill into a drink via a matchbook and which suit pocket best hides an object. Assumed destroyed in a 1973 records purge, they resurfaced during declassification and are now free to read in full.