"The One That Got Away" is a song by American singer-songwriter Katy Perry from her second studio album, Teenage Dream (2010). The song was produced by Dr. Luke and Max Martin, both of whom also co-wrote the song with Perry. The song is a mid-tempo pop ballad about a lost love. It features a reference to the rock band Radiohead, and compares the strength of the relationship to that of Johnny Cash and June Carter Cash. The song was released on September 30, 2011, by Capitol Records as the album's sixth single.

Katheryn Elizabeth Hudson, known professionally as Katy Perry, is an American singer, songwriter, and television personality. She is known for her influence on modern pop music and her camp style, being dubbed the "Queen of Camp" by Vogue and Rolling Stone. At 16, Perry released a gospel record titled Katy Hudson (2001) under Red Hill Records, which was commercially unsuccessful. She moved to Los Angeles at 17 to venture into secular music, and later adopted the stage name "Katy Perry" from her mother's maiden name. She recorded an album while signed to Columbia Records, but was dropped before signing to Capitol Records.