Songfacts®:

• This sweet pop ballad about lost love finds Katy and her guy get matching tattoos on her 18th birthday. Later she hears that he's got his tattoo removed, so she knows the relationship is over. The singer penned the song with Dr. Luke and Max Martin with the latter two also producing the track.
• The song finds Perry calling out her love for Radiohead ("We make out in your Mustang to Radiohead") and Johnny Cash ("I was June and you were my Johnny Cash").
• The song was chosen to be the sixth single from Teenage Dream. "I'm so pleased to select 'The One That Got Away' as my sixth single because this song shows a very different side of me that I haven't shown with my past singles on this record," said Perry. "I think that everyone can relate to this song. I wrote (it) about when you promise someone forever, but you end up not being able to follow through.It's a bittersweet story. Hopefully, the listener learns from hearing it and never has to say they had 'The One' get away."
• The Floria Sigismondi directed music video finds Perry reminiscing about her old flame.
  
  The singer's ex is played by Mexican actor Diego Luna whose resume includes portraying Jack Lira in Milk, as well as supporting parts in Frida and Before Night Falls. In 2016 Luna played one of the rebels in Rogue One: A Star Wars Story. He told People that prior to the blockbuster movie, the Katy Perry video was what he was best known for.
  
  "This whole world of pop - it's so intense and it got everywhere. I became 'The Guy from the Video,'" he said. "In places where I used to just walk around without getting any attention, suddenly people were like, 'Oh my God, the guy from the video!'"
• The song peaked at #4 on the Hot 100 in its original chart run despite the price of the single on iTunes being lowered from $1.29 to 69 cents in an attempt to encourage more buyers. In a calculated move to make the song a record breaking sixth chart-topper from one album, Perry recorded a remix with a new verse by rapper B.o.B. However this new version only pushed the song up one place to #3 making the song truly the #1 that got away.
• The song might have failed to reach the peak position on the Hot 100 but it did become the sixth # 1 from Teenage Dream on the radio-based Billboard Pop Songs chart. Previously, no album had yielded more than four Pop Songs chart-toppers.
• According to a source close to Perry, this song was inspired by the actor Jonathan Lewis, whom she dated for around 18 months in 2005 and 2006. Lewis, who was found dead in the driveway of his home on September 2, 2012, was best known for playing the character Kip "Half Sack" Epps in the US TV series Sons of Anarchy and Dennis 'Chili' Childress in the teen drama The O.C..
  
  The source told US Weekly that Perry also wrote "Circle The Drain" about her one-time beau.
• The teaser for the video was narrated by Stevie Nicks. Speaking about the first time she saw the clip, she said it reminded her of her split from former lover and Fleetwood Mac bandmate Lindsey Buckingham.
  
  "About a minute in, I just began to cry. It reminded me of my own life and losses, and of the last fight that Lindsey Buckingham and I had."
• Katy Perry was romantically linked with the singer Josh Groban in the late 2000s. Speaking to James Corden in 2017, during her Witness World Wide live stream, Perry said: "'Who's the song 'The One that Got Away' about?' - that's Groban... He's one of my good friends."
  
  Asked about Perry's claims on the September 20, 2018 episode of Watch What Happens Live Groban admitted that he dated the singer but having listened to the lyrics, he would be surprised if he was the inspiration, as he doesn't have a Mustang or any tattoos.