Based on a lost love, "Again" was included as the closing song to her 1993 box-office film debut in Poetic Justice. While not included on its soundtrack album, the song was nominated for Best Original Song at the 66th Academy Awards, where Jackson performed the song live. The janet.jazz-funky track "Funky Big Band" appears on the single as a B-side. A French version of the song was also recorded by Jackson and appears on the CD single as well as the limited edition of the janet. album. The track became her seventh number one on the Billboard Hot 100 chart, staying atop for two weeks.
"Again" is set in common time with a key of C major. Jackson's vocal chords ranges between the tonal nodes of high-tone G3 to low-tone D5. The song is in a moderate tempo of 64 beats per minute with the chord progression being set like C–G–Am–F–C–Dm7/G in the first verse and C–E–Am7–D9 in the chorus.
The music video for the song was directed by Jackson's then-husband René Elizondo, Jr. in 1993. It features actor Gary Dourdan as Jackson's lost love, with Jackson writing in her diary as she reminisces about her love through flashbacks. The alternate version of the video contains scenes from Poetic Justice playing on a television. The original video appears on the 1994 compilation janet. and the 2004 DVD From janet. to Damita Jo: The Videos, while the Poetic Justice version is included on the 2001 DVD edition of All for You.