"Star Girl" is the second single from McFly's third studio album, Motion in the Ocean, which was released in the UK on 23 October 2006. The song was the band's sixth no. 1 single in the UK, staying in the Top Ten for two weeks. In 2009, the song was played in space to wake up the astronauts on the space station, with thanks to a successful Twitter campaign started by band member Tom Fletcher, asking NASA to play the song in space.
"Star Girl" was written by McFly, Jason Perry, Julian Emery and Daniel P. Carter. The single features a live recording of "Silence is a Scary Sound" from the Wonderland Tour 2005 DVD. "Silence is a Scary Sound" was written by McFly bassist Dougie Poynter when he was 14 years old. The single also includes the first track from the Motion in the Ocean album, "We are the Young". The song was inspired by a dream Tom Fletcher had, about falling in love with an alien woman. The song was originally called 'Good Night', but the band felt the lyrics didn't fit. Tom had a dream about writing a massive, Westlife style song written about falling in love with an alien women so he decided to replace the 'Good Night' lyrics with the new lyrics hoping it would be a bigger success than the song he wrote in his dream.
On 15 June 2009 McFly made a surprise guest appearance at the Jonas Brothers concert at Wembley Arena, where they performed 'Star Girl' along with the Jonas Brothers. Since the start of 2010, Star Girl was played every Friday morning on The Chris Moyles Show on BBC Radio 1 in a feature called "McFlyday", on the final Chris Moyles Show broadcast 14 September 2012 the band re-recorded the track with altered lyrics relating to Chris Moyles and BBC Radio 1.
The video featured home footage of the band at Danny's house in Bolton as well as a performance scene filmed in South London in front of a live, fan-based audience. The home footage featured the boys sending Dougie Poynter into "space" and testing out a variety of Don't-Try-These-At-Home type stunts, Later in that video Dougie is in a spaceship eating a floating on air malteaser.