Open sesame

"Open sesame" (French: Sésame, ouvre-toi; Arabic: افتح يا سمسم, romanized: iftaḥ yā simsim) is a magical phrase in the story of "Ali Baba and the Forty Thieves" in Antoine Galland's version of One Thousand and One Nights. It opens the mouth of a cave in which forty thieves have hidden a treasure.