* CreatorBacklash: Brian Garfield, the author of the original novel, sued the filmmakers for twisting the source material (ironically, the point of Garfield's novel was that vigilante tactics ''weren't'' the solution). You can probably guess from the four subsequent sequels that he lost.
* WhatCouldHaveBeen:
** Music/FrankSinatra, Creator/ClintEastwood and Creator/SteveMcQueen turned down the role of Paul Kersey.
** There were plans for a sixth film with the subtitle ''The New Vigilante''.
** There were plans to bring back Kersey's girlfriend from the second film for a cameo in the third or fourth--to be killed off, of course.