Open Sesame

Clyde Langer tried saying "open sesame" to get the Verron puzzlebox open. (TV: The Temptation of Sarah Jane Smith) The Fourth Doctor tried it too when trying to open a door in the Chancellory on Gallifrey. He soon found out that, while it did work on a voice print, the phrase that unlocked it was, "There's nothing more useless than a lock with a voiceprint." (TV: The Invasion of Time)