Our world is changing. The mass extinction we feared... has already begun... and we are the cause. We are the infection. But like all living organisms, the earth unleashed a fever to fight this infection: its original and rightful rulers, the Titans. For thousands of years, these creatures have remained in hiding around the world. And unless all the Titans are found, our planet will perish, and so will we. They are the only guarantee that life will carry on.
~ Emma Russell explaining her goal to awaken the Titans.
Long live.. the king.
~ Emma's last words before she dies from her injuries after being injured by King Ghidorah.
Dr. Emma Russell is a major antagonist-turned-anti heroine of the 2019 film Godzilla: King of the Monsters. She is a scientist from Monarch who defects to Alan Jonah's terrorist group and after her son Andrew was lost during Godzilla's fight with the M.U.T.O.s in 2014, Russell became convinced that humanity was a plague and that the Titans were the only way to restore order and balance to the planet.
At some point prior to the movie, Emma contacted Alan Jonah and his ecoterrorist group and offered to give them the ORCA her husband had designed so they could use it to awaken the other Titans. After Jonah and his men killed the other members of Emma's MONARCH expedition, they retrieved Emma and her daughter Madison along with the ORCA.
Russell then traveled with them to Antarctica where they intended to use the ORCA to awaken "Monster Zero". However, while there, they were attacked by MONARCH forces and Emma found herself faced by her ex-husband, Mark Russell. Mark attempted to convince Madison to come over to him but before he could do so Emma activated the detonator and set off the explosives around the area Monster Zero was contained in, releasing King Ghidorah. Emma and the rest of Alan Jonah's forces then made their escape on helicopter as Ghidorah rampaged and attacked the Monarch forces.
After Ghidorah's escape, Emma contacts MONARCH for a negotiation, claiming that by awakening the Titans, she can restore the natural order and revert the wrongdoings of humanity.
However, when they got back to Alan Jonah's base, Jonah's team discovered that King Ghidorah was already awakening the other Titans and commanding them to wipe out the humans and terraform the world to his will. Though Jonah was fine with this, Emma began to have doubts. Emma later discovered that her daughter Madison had stolen the ORCA and was heading to Boston to transmit a signal to disrupt Ghidorah's communication with the other Titans and get them to stop attacking.
Emma then went to Boston herself to rescue her daughter, encountering Mark and the remaining members of MONARCH. While there, Emma ended up sacrificing herself to use the ORCA to lure away King Ghidorah and give Godzilla time to recover, resulting in Ghidorah killing her. Emma's body was then disintegrated after Godzilla, now in a fiery form, activates two nuclear pulses that vanquish Ghidorah's wings and two side heads before stomping on top of the Titan's body and crushing it in an electrical explosion.
Emma Russell is the first female villain (and possibly third human villain) in the MonsterVerse film series, with Preston Packard and Alan Jonah as the male human villains in the film series.