Mercy Graves is a supervillain appearing in multimedia and American comic books published by DC Entertainment and DC Comics. Created for the DC Animated Universe (DCAU), she first appeared in 1996 on Superman: The Animated Series as the personal assistant and bodyguard of Superman's archenemy Lex Luthor, returning in Justice League and Justice League Unlimited, voiced by Lisa Edelstein. She has since been introduced into comic books published by DC Comics.

In live-action, the character has been played by Tao Okamoto in the 2016 DC Extended Universe (DCEU) film Batman v Superman: Dawn of Justice, Rhona Mitra in the fourth season of the television series Supergirl, and by Natalie Gumede in the second and fourth seasons of the series Titans on DC Universe and HBO Max. Additionally, a character based on Graves named Tess "Mercy" Mercer appears in Smallville, portrayed by Cassidy Freeman.

Mercy Graves was created for Superman: The Animated Series as a tough young woman with a checkered past, serving as Lex Luthor's personal bodyguard and chauffeur. Graves was originally the leader of a gang of female thieves and first encountered Luthor after attempting to steal his briefcase. Though Graves failed, an impressed Luthor recognized her ruthlessness and street savvy and took her in.

An alternate reality version of Graves appears in the episode "Brave New Metropolis". After Luthor and Superman turned Metropolis into a police state, Graves became the commander of Luthor's law enforcement group.

In the Justice League episode "Tabula Rasa", it is established that Graves took over LexCorp following Luthor's imprisonment. Graves is hesitant to return ownership to Luthor because she feels their former relationship was not an equal one. Graves grudgingly assists Luthor's escape from the Justice League, but his deceitful manipulation of another devoted servant causes Graves to see their years together in a different light. After Luthor is recaptured, Graves hangs up on Luthor when he requests help in obtaining a lawyer and doctors to treat his kryptonite-caused cancer. Nonetheless, Graves returns to Luthor's side in the Justice League Unlimited episode "Clash".

Mercy Graves first appeared in the main DC Universe continuity in Detective Comics #735 (August 1999), during the No Man's Land storyline. This version is blonde and often works with an additional bodyguard, Hope. It is suggested that the two may be Amazons, with Prometheus claiming Graves to be an Amazon in the series Justice League: Cry for Justice.

Mercy Graves appears in the Infinity, Inc. series, where she intends to atone for her past deeds. In issue #8, she takes on the moniker "Vanilla" and wears a costume equipped with a special mask that keeps her identity hidden. However, she leaves after almost beating a man to death, accepting the fact that she is not "hero" material.

In The New 52, Graves is reintroduced as Luthor's Asian American personal assistant who manages LexCorp in his absence.