21:13 is the twelfth song and twenty-third track on the 2003 album In Keeping Secrets of Silent Earth: 3. It is preceded by eleven tracks of silence, varying in length, separating it from the previous song on the album, The Light & the Glass. This, along with not being noted on the album's tracklisting, makes it a secret track. This song reprises two other tracks in The Amory Wars, namely Time Consumer and IRO-bot, both from the previous album The Second Stage Turbine Blade. It is currently the longest-running Coheed and Cambria song.