Fly by Night or Fly-by-Night may refer to:
Film and television Fly-by-Night (film), a 1942 American thriller Fly by Night (TV play), a 1962 Australian TV play Fly by Night, a 1992 film directed by Steve Gomer Fly by Night (film), a 2019 Malaysian crime thriller Fly by Night (TV series), a 1991 Canadian adventure series starring David James Elliott "Fly by Night" (Mighty Max), an episode of the television series Mighty Max
Fiction Fly by Night (Hardinge novel), a 2005 children's novel by Frances Hardinge Fly-by-Night (Peyton novel), a 1968 children's novel by K. M. Peyton "Fly-by-Night", a short story by Larry Niven included in the Man-Kzin Wars collections "Fly-by-Night", a mysterious flower in the Japanese animated film Mary and the Witch's Flower
Music Fly by Night (album), a 1975 album by Rush "Fly by Night" (Rush song), 1975 "Fly by Night" (Andy Williams song), 1961 "Fly by Night", a song by Ian Anderson from Walk into Light "Fly by Night", a song by Matt Bianco from Matt Bianco Fly by Night (musical), a musical written by Will Connolly, Michael Mitnick, and Kim Rosenstock
Other uses Fly by Night Theatre Company, an Irish theatre company