Thoughts on a Clock

"Thoughts On A Clock" was a poem by Eric Ritchie Junior. Extracts of it went,
 * ''And now it's time for one last bow
 * ''Like all your other selves
 * ''Eleven's hour is over now
 * ''The clock is striking twelve's.

This was included in at least one of the Christmas crackers that Ellie Oswald bought for Christmas 2013, where she was invited to a Christmas dinner at her daughter Clara Oswald's place and supposed to get to know her boyfriend.

Clara brought the cracker with her to the town Christmas, opened it with the Eleventh Doctor and revealed extracts of the poem. The Doctor, who had hoped for a 'Knock, knock' joke, failed to realize it's meaning in the circumstances and claimed 'I don't get it.' (TV: The Time of the Doctor)