Songfacts®:

• Coldplay unexpectedly posted this track on their website on February 25, 2014 after directing fans there with a message on Twitter. They flagged up the new tune by telling fans "Something new at 0:00 in Ulaanbaatar", then they posted the video at what would have been midnight in the Mongolian capital.
• This marked a more stripped back, electronic sound for Coldplay and was written by the band with Jon Hopkins. The London-based producer writes and performs his own melodic electronica and dance music and has twice been nominated for a Mercury Priz for his albums, in 2011 for Diamond Mine and 2013 for Immunity.
  
  Hopkins has collaborated with Coldplay before co-producing two tracks on their Viva la Vida album ("Life In Technicolor" and "Death And All His Friends"), as well as being credited for "light and magic" on their Mylo Xyloto disc.
• The song is built around an original composition written in 2003 by Hopkins. It was recorded by Coldplay in 2013 during sessions for their sixth studio album at their The Bakery and The Beehive studios in North London. Hopkins recalled to Billboard magazine: "Chris (Martin) had been working with this harmonizer sound that had nothing to do with me. My track was playing in the background and he just quickly wrote that whole bit on top. It was kind of really an amazing moment, because we all had a feeling that there was another seed of a great song being born."
• The black-and-white atmospheric video features the band walking through a forest and was shot in negative exposure. The visual was directed by Mary Wigmore, who is the godmother of Chris Martin's daughter, Apple. She previously worked with Coldplay on the clip for their 2006 "The Hardest Part" single.
• A remix by Giorgio Moroder was released on April 21, 2014 as a digital download single. The Italian disco legend's reworking of Coldplay's chilly tune runs for an epic eight-and-a-half minutes.