Brendon Urie born 1987 said that idea of "The Ballad of Mona Lisa" was from four years ago, it was sitting on a flash disk but ended up being good in the whole process.
"A few of the ideas  like "The Ballad of Mona Lisa", specifically  was from an idea I had probably four years ago, before we even started touring on Pretty. Odd., and it was just sitting in my laptop collecting figurative dust on my hard drive, not really doing much," said Urie. 
