"Who the hell is Elizabeth Keen?"

Elizabeth Scott Keen (born in Moscow as Mascha Rostova) was a profiler for the FBI. She has just graduated from Quantico when she is asked by Assistant Director Harold Cooper to come work for this special task force in order to work with Raymond Reddington. She is the only person whom Reddington is willing to work with. She has yet to learn why, but he has told her that it has something to do with her missing father. She has a mysterious and traumatic past. Her wrist bears a large scar from a fire she was trapped in as a child and her only memory of her biological father is of him rescuing her from the fire. Reddington admitted to blocking her memories of the fire. She eventually regains her memory of the event when she killed her father to protect her mother. Her marriage to Tom Keen appears to be idyllic, but it begins to unravel when she discovers evidence that he is not the man he appears to be. She also learned that she was the key to unlocking the mysteries of the Fulcrum, and that she had unknowingly had the Fulcrum itself in her possession since childhood. With the help of Leonard Caul, she deciphered the Fulcrum's contents and confronted the Director with them. She was then unknowingly infected with a customized biological weapon by the Cabal and tricked into infecting their target, Senator Hawkins. The Cabal then framed her for Hawkins's assassination and for being a Russian spy. After shooting Tom Connolly, Liz goes on the run with Red. After several weeks Liz is arrested by Ressler and brought over to the Post Office in anticipation for her trial. Red cut a deal for Liz with Laurel Hitchin, Liz had to plead guilty to involuntary manslaughter and gets three years probation. Though she would be free, Liz could never return to the FBI. Liz reluctantly took the deal in the end as Red ensured she'd remain part of the task force as an asset like him. Liz was publicly exonerated by Laurel Hitchin. Liz has difficulty adjusting to no longer being an FBI agent. After being beaten up by a man who thought she was a traitor, she is hospitalized and discovers she is pregnant. She accepts Tom's marriage proposal, hoping to start a family with him. Liz and Tom's wedding ceremony is interrupted by Mr. Solomon, who pursues them relentlessly. Liz is injured during the chase, forcing Red's doctor to perform an emergency C-section to save her baby. Liz tragically dies due to complications with the C-section and the inability to reach a hospital on time. Or so they want us think. It is revealed that Liz's death was faked by Mr. Kaplan, Nik and Tom to keep Agnes safe, so she wouldn't grow up in Red's world. Liz is alive and well and she is hiding in Cuba where she is waiting for Tom and Agnes to arrive. She is taken by a man named Alexander Kirk, who reveals himself as Constantin Rostov, Liz's father.
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