"Greater love hath no man than this, that a man lay down his life for his friends."
A character does something incredibly brave and is
killed, maimed, or otherwise irrevocably harmed doing it.
A bad character who was once good can redeem himself in the last act by
Taking the Bullet that was meant for
The Hero, thus expunging all his previous evil, avoiding forcing
The Hero to arrest or confront him, and avoiding any real life penalties like disgrace and jail. This is like
Redemption Equals Death. In this case, the death and redemption come in a single act.
There are essentially three kinds of
Heroic Sacrifice:
See
Taking the Bullet,
Self-Destructive Charge,
You Shall Not Pass,
Take Me Instead,
Someone Has to Die and
Sealed Evil in a Duel for specific types of
Heroic Sacrifice. Usually requires that a character be
Not Afraid To Die. If the
Heroic Sacrifice was pre-planned, it's a
Self-Sacrifice Scheme. Often preceded with a
Sneaky Departure from the team, or a
More Hero than Thou dispute.
A Friend in Need often requires it. Contrast
My Revenge Is Mercy, when a dying villain decides to save a life. The
Doomed Moral Victor fights a battle where the outcome is clear from the beginning. If the character has time to say some last words before dying, they often do so in an
Obi-Wan Moment. Often a
Dying Moment of Awesome.
Compare and contrast
Zero Approval Gambit (where the hero sacrifices his good name instead of his life),
My Death Is Just the Beginning,
Senseless Sacrifice,
Suicide Mission and
Stupid Sacrifice.
Examples: