Working for Professor Strange
Dr. Peabody received a body bag at her lab in Indian Hill and told the workers that Professor Strange is interested in the corpse. She then opens the bag, surprising herself when she sees Theo Galavan's corpse with an umbrella stuck in his mouth.
When Hugo Strange takes his secret elevator at Arkham Asylum to get to Indian Hill, he meets with Ethel Peabody to learn the status of the experiments. She tells him a certain chemical needs replacing and that Bridgit Pike is not cooperating with the experiments. Strange then receives a newspaper detailing about how Mr. Freeze has found a way to perfect the cryogenics which he has been working on for a long time to handle for his experiments.
At Indian Hill, after Hugo Strange fruitlessly attempted to extract Fries' cryogenic from the body of one of his victims, is approached by Peabody who informs him of the transfer request made by the GCPD. Ms. Peabody has her employees forcibly drag Oswald Cobblepot to a chair with restraints and issues several threats, specifically to Ms. Peabody. However, Peabody disregards the threats and puts a helmet on Penguin for his rehabilitation to begin. After Peabody activates the electricity to shock Oswald, he wakes up in the game room of the Asylum believing that it was all about a bad dream. He is then convinced by Mrs. Peabody to play a game of duck, duck, goose with the other inmates. At that time, the GCPD entered the asylum to transfer Nora Fries. Peabody escorted Leslie and Nora to the medical wing of the asylum.
Strange decides to give Oswald a certificate which stated that he was cured and was legally sane, and could, therefore, be released. At that Cobblepot has a burst of joy and returns to his room to collect his belongings, but Ms. Peabody disagrees with the idea and suggests warning the police about Penguin's release. Somewhat annoyed, Hugo reveals that Oswald was an experiment which he had deeper plans for, and at the moment could not reveal them to her for her own safety. Notwithstanding, Ms. Peabody finds his explanation ridiculous and as what could be deeper than the monsters they were creating in the Indian Hill facility below.
Ethel was present when Hugo Strange was doing group therapy which Barbara Kean was part of. After Barbara Kean was released from Arkham, Ethel is told by Hugo that he did this in order to study her.
Ms. Peabody informs Hugo Strange that someone in Wayne Enterprises was seeking information about Karen Jennings and Pinewood Farms. Later, Ms. Peabody informs Strange that Victor had seen Jim Gordon and a boy, who Strange deduced was Bruce Wayne. Suddenly they are alerted by an alarm in the room about patient's 44. Upon arrival to the Indian Hill facility they see a resurrected Theo Galavan brutally attacking his medical examiners and orderlies, and recites lines from the Order of St. Dumas, screaming "Azrael" towards the end.
Nygma overhears Peabody and Strange talking about how Gordon may become a big problem to their current plans. Nygma calls them over and offers his help in taking Gordon down, but Strange refuses, though Nygma unintentionally gives him an idea of how to solve his problem with Theo Galavan. Later, Professor Strange and Ms. Peabody watched as Theo watched a video teaching him about the Order of St. Dumas in the reanimation lab. Strange told Peabody that Galavan's mind couldn't reconcile death and rebirth until he gave it a grander context. In Arkham's cafeteria, Ed is still upset about how Strange had dismissed him earlier. Ethel arrives and asks Aaron to come with her. As she closes the door, Ed holds it open with a newspaper. He realized that Strange was hiding something, and follows Ethel and Aaron in a corridor and discovers that there's a secret passage in the hallway. Aaron is brought into the lab, and Strange orders Theo to vanquish him, as a test. He then points to a metal case and tells him that it contained everything he needed to defeat Helzinger, though instead of opening it, he takes the case and knocks Aaron unconscious with it. Strange then orders Theo to open the case, and he finds a sword, which Professor Strange tells him is the Sword of Sin, though Peabody notes to Strange that it is only a replica. Professor Strange then orders Theo to kill James Gordon.
While in Indian Hill, Selina Kyle overhears a conversation between Strange and Peabody in which they reveal themselves to be responsible for having sent Azrael after Gordon. Strange then tells Peabody that the facility needed to be shut down, and all patients moved to a new location. Selina enters a training room where she sees her old friend, Bridgit Pike, who is dressed in a new fireproof suit prepares to burn her thinking she was one of the test subjects sent by Professor Strange. Selina tries to remind her they were friends and tells her about her accident, but Bridgit ignores her as she was suffering from amnesia. Failing to reason with Bridgit, Selina tries to escape the room but all the exits are locked. Though Selina pleads with Bridgit not to attack her, Bridgit tells her that her name was Firefly before using her flamethrower. Inside the control room, Strange and Peabody watched the events unfold.
Strange and Peabody revive a patient named Basil, who after being resurrected touches his face, and notices that it has the ability to stretch. Unfortunately, the patient remembers nothing of his past life. Outside the room, Peabody warns Strange that their employers were going to shut them down. However, Strange is not deterred as you couldn't order scientific discoveries. Later, Nygma is cornered in a cell, with a cannibalistic inmate, Stirk. However, he pleads with Peabody to let him out, offering to help stop Jim Gordon and the GCPD. Strange and Peabody observed the recently resurrected Fish Mooney in her cell from a security monitor. The two then theorized why Fish was able to come back with her memories, but Strange said that their employers would be pleased as they created the first true reanimate. Peabody then asked Strange whether he had thought about Nygma's offer, and he told her that he'd give Nygma a chance. She then informed Strange that Bruce Wayne was outside of Arkham asking for him. Peabody took Lucius Fox on a tour around the asylum, on his request. Lucius informed Gordon that if he saw anything suspicious he would mark it with white chalk. Lucius eventually finds the entrance to the Indian Hill facility using his device and marks the wall with white chalk before continuing on the tour with Peabody.
Peabody is taken control of by Fish Mooney and helps her escape. She attempts to stop Strange from getting the bomb to blow up, but he knocks her out. When she wakes up she is asked how to disarm the bomb, as Lucius and Gordon aren't able to come up with an idea on how to diffuse it. Peabody simply says: "water." With a few seconds left on the timer, Gordon throws water on the circuits of the bomb and it miraculously turned off, afterward, he and Lucius realize that Peabody was actually asking them for water for her to drink.
Jim later encountered Peabody who is under house arrest in exchange for testifying against Strange. Gordon states that Fish might be after her. Gordon was actually using Ethel as bait when two Indian Hill escapees attack. They defeat Gordon and the two of them make off with Ethel while one with retractable wings is left to fight Gordon. In the presence of Fish, Ethel states that she knows that her abilities are causing her body to reject her new cells. She states that she can't re-order her DNA. Upon being touched by Fish Mooney, Ethel states that Strange might be able to fix her. Mooney then has her fellow escapee Marv drain Ethel's youth, causing her to die of old age.
Lucius informs Gordon that the reason for Fish kidnapping Peabody was to see if she could cure her. Lucius then shows Gordon Peabody's corpse and tells Gordon that he believes that Peabody didn't have a cure for Mooney, so she had one of her monsters kill her, as she was no use to her.
Ethel Peabody, like her boss, was immoral if not indifferent to her patients as she saw no qualms over torturing and mangling mentally troubled people to advance Hugo Strange's scientific research and genuinely seemed to feel that the end would eventually justify the means. Her indifference was displayed when upon discovering Theo Galavan's body was desecrated by an umbrella forced down his throat, she was unfazed but calmly stated that it was "unusual". Peabody also had a slightly sadistic side to her personality as she only smiled and laughed throughout whilst Penguin was being submitted to brutal mental torture.