Mercy Graves was Lex Luthor's bodyguard and personal assistant.
Lex's right-hand woman
After Hanford Technologies is successfully exposed by Daily Planet reporter Lois Lane, Mercy accompanies Lex Luthor to a construction site of the company, where he announces that LexCorp is purchasing all of Hanford's holdings (including the site), as well as retaining all of Hanford's employees, as he claims that the employees should not suffer from the immoral actions of their former CEO. Lex proceeds to admit that despite his failings, Mark Hanford had been a good CEO, who's big mistake was selling illegal Kryptonian technology. Later, in the privacy of his car, only Mercy hears Lex finish - because there are so many more interesting things that could potentially be done with it.
Mercy later also accompanies Lex to the latter's public groundbreaking ceremony to rebuild LexCorp Tower. When they reach the privacy of their car, Mercy praises the expertise with which Lex handled certain complicated questions from the reporters at the event, notably answering that he doesn't know enough about Superman to make a comment.
Lex, however, claims that there was nothing to "handle", as he was telling the truth - he does in fact know little about Superman. However, as Lex and Mercy return to the former's LexCorp facility, he continues, saying that he has been "working on changing that." With those words, Lex enters a private room with CCTV screens (displaying the corpse of General Zod, the Fortress of Solitude, and a Kryptonian DNA double helix), asking Mercy to make sure he isn't disturbed, as he plans to spend the rest of the day in there.
Monitoring for Lex
Mercy is shown in the first US capital hearing, in order to monitor that Lex's covert pawn Kahina Ziri carries out her mission. Mercy is later seen escorting June Finch and Barrows to a meeting with Lex. Upon Lex coming to an agreement with Barrows, she delivers the body of the deceased Kryptonian Zod to Lex.
Mercy is present at the charitable function Lex holds at his Metropolis villa. There, she notices Bruce Wayne sneaking about suspiciously, and decides to follow him. She finds him downstairs next to a computer server and inquires as to what he is doing there. Bruce claims he was looking for the bathroom which she says is upstairs. Bruce (in order to convincingly appear as a playboy billionaire) also compliments Mercy on her stylish shoes as she walks off.
Later, Mercy is present at the US Capitol again, with Lex Luthor and Wallace Keefe to attend the Senate committee hearing for Superman. After he has a brief talk with June Finch, Lex instructs Mercy to enter the committee chamber and reserve him a seat. However, Lex never arrives and when a bomb hidden inside Keefe's wheelchair is detonated, Mercy and all others present perish, bar the invulnerable Superman.
Mercy is fiercely loyal to Lex Luthor, whom she seems to admire, and Lex, in turn, greatly respects Mercy's efficiency, considering her his closest ally and confidant, and revealing to Mercy most of his grand supervillain plans. She is a lady of few words, instead efficiently carrying out her duties and obligations. Despite Lex greatly valuing her, she is ultimately shown to be disposable to him, as Lex remorselessly decides to have her killed at the US Capitol bombing, thus ridding himself of the loose end tying him to Wallace Keefe.
- Originally, Mercy Graves made her first debut in Superman: The Animated Series. Due to the popularity of her character, she was eventually adapted into the DC Comics universe.
- When first introduced in the comics, Mercy was originally revealed to be an Amazonian in disguise. Her character was then rebooted as the human assistant of Lex Luthor.
Behind the scenes
- When DC and WB originally announced Okamoto's involvement in Batman v Superman: Dawn of Justice, in 2014, they labeled the character she was playing as "created in this fictional universe". However, on July 27, 2015, DC confirmed on their official Comic-Con Trailer Breakdown, that she is, in fact, playing Mercy Graves.