God Rest Ye Merry, Gentlemen

"God Rest Ye Merry, Gentlemen" was an ancient Earth Christmas carol. It was this song that was being played by a group of robotic Santas before they attacked Rose Tyler and Mickey Smith on Earth. (TV: The Christmas Invasion) A group of children were singing this song when the Tenth Doctor arrived in London on Christmas Eve 1851, just before his encounter with the Cybermen. (TV: The Next Doctor) The song was also played by a brass band shortly before the Tenth Doctor regenerated. (TV: The End of Time)

The melody of the carol was the same as that of the "Venusian lullaby" occasionally used by the Third Doctor to lull his foes into a state of tranquility. (TV: The Dæmons, The Curse of Peladon and PROSE: Venusian Lullaby)