This was featured in the final scene of the John Hughes-directed movie Pretty in Pink, and OMD wrote it specifically for the film. In our interview with Andy McCluskey of OMD, he explained: "We were delighted to be asked by John, and went to the set where Molly and John Cryer were shooting. Unfortunately, the original song that we wrote didn't fit after they changed the whole ending (the original ending had Molly Ringwald's character choosing Duckie, who was played by Cryer, instead of Andrew McCarthy's Blane). We had 2 days to write a new track at Larabee Studios in L.A. We worked until 4 a.m. writing a rough version and sent a motorbike to Paramount. John heard it, liked it, and our manager phoned us at 8 a.m. and told us to go back in and mix it. That's how 'If You Leave' Happened! The song had to be 120 BPM cos that's the tempo of 'Don't You (Forget About Me),' which is the track they actually shot the prom scene to. Unfortunately, the editor obviously had no sense of rhythm because they are all dancing out of time in the final film. It was cool to be in the film for so long and fantastic to go on the red carpet at the Chinese theater at the premier."
Thanks to its use in the movie, this was the biggest hit for OMD in America. They did chart in the US with "So In Love," "(Forever) Live and Die" and "Dreaming," but are far more popular in their native England. McCluskey told us: "To many Americans, we are a one hit wonder, even though we had several other hits. Nothing as big as 'If You Leave.' It's a blessing to have such a big hit, but a shame that it overshadows so many other good songs for the US audience. We have many European fans who hate the song..."