Mr. Blue Sky

Jeff Lynne wrote "Mr. Blue Sky" after locking himself away in a Swiss chalet while attempting to write Electric Light Orchestra's follow-up to A New World Record. The weather worked against him at first. It was dark and misty for two weeks, and he came up with nothing, unable to see any countryside for the first four days. Then everything cleared, the sun shone, and he was greeted by an enormous view of the blue sky and the beautiful Alps. In the following two weeks he wrote "Mr. Blue Sky" and thirteen other songs. He later recalled writing the words down at the chalet and described the track as possibly his most well-known song, noting its nursery-rhyme appeal to children.

The song appeared on Out of the Blue, ELO's 1977 double album, as the fourth and final part of the "Concerto for a Rainy Day" suite on side three. Released as the album's second single, it reached number 6 on the UK Singles Chart and number 35 on the US Billboard Hot 100. Promotional copies were pressed on blue vinyl, matching the album itself. The arrangement featured a cowbell-like sound credited to drummer Bev Bevan, who produced it with a fire extinguisher.

Bassist Kelly Groucutt offered a different account of the song's origins. In a 1983 lawsuit against Lynne, he alleged that he had written the middle section but never received an official credit for it.