Songfacts®:

• The lead single from Four, the song was penned by Louis and Liam with frequent One D songwriters Ed Drewett, Wayne Hector, Julian Bunetta and John Ryan. The same six songsmiths also wrote the Midnight Memories track "Little White Lies" together.
• This was made available everywhere apart from Britain on September 29 2014. It was released in One Direction's home country a fortnight later. A remix of the recording by Liam (dubbed as the Big Payno Remix) was made the B Side in the UK.
• The song is a piano ballad that has the guys lamenting about those who want to steal their girlfriends away. Julian Bunetta revealed to MTV News that there were actually several girls that inspired the track. "It's based on everybody's experience," he said, "you have six guys in a room that have all been in love before and we all have jealousy - some are better at hiding it than others, but we don't like when people hit on our girlfriends."
  
  "But it was more of a joyous thing, it just speaks to how happy you are with this person," Bunetta continued. "If you have something great, everyone is going to try and take it from you. And that also speaks to the fanbase, I think, 'cause of other groups [trying to steal the 1D fanbase]... there are a lot of layers."
• Bunetta revealed that the idea behind the song happened pretty randomly. "I think, if I recall correctly, we were playing a drum beat and it just sort of came out," he recalled. "Somebody said that line and it was like, 'Woah, yeah I relate to that,' and we all looked around and was like, 'Yeah, I like that, I can totally relate to that.'"
• The piano at the beginning of the song is similar to both New Found Glory's 2006 track, "It's Not Your Fault" and Journey's 1983 single "Faithfully." New Found Glory's frontman, Chad Gilbert, picked up on the resemblance and jokingly tweeted:
  
  Props to the @onedirection "steal my girl" single for reworking the "it's not your fault" piano part into a top 40 single. Let me get a cut.
  
  Bumetta wasn't aware of the resemblance until he read the song reviews. "When we sat down and played the piano lick, nobody had any references in their head about what they wanted to write or anything and then I saw all the things about that [Journey song]," he told MTV News. "At the end of the day, the lyric and the melody have nothing to do with any other song that I have ever heard. Sometimes there's only so many things you can do with a piano at that tempo."
• The song's music video was directed by Ben and Gabe Turner, who both produced the 2011 TV movie One Direction: A Year in the Making. The clip features comic actor Danny DeVito as the visual's fictional director and we see the It's Always Sunny in Philadelphia star direct the guys through some bizarre antics with a juvenile chimpanzee, sumo wrestlers, acrobats and a marching band.
• One Direction became the first group to have their first four albums debut at #1 in the US when their appropriately titled long player, Four, topped the Billboard 200 album chart in its first week.