- "The fact is, you've lost sight of your mission. Sending men with swords into Gotham. Freaks armed with freeze guns."
- —The White-Haired Woman to Hugo Strange
Hugo Strange welcomes a familiar face to Gotham after he resurrects Fish Mooney in Indian Hill. Later, Bruce discovers a friend is in danger and teams up with Gordon, Alfred and Lucius, while uncovering more of Strange's experiments.
At Indian Hill, Selina Kyle runs through the room attempting to hide from Firefly, who was attempting to shoot her with a flamethrower to kill her. Fortunately, Selina is able to sneak up behind Bridgit and knock her unconscious. Meanwhile, Bruce Wayne waited on top of a rooftop for Selina, but after Ivy Pepper arrives instead, he realizes that Selina is in trouble. At the GCPD, Detective Bullock, in his role as acting captain, informs the media about the death of Azrael caused by unknown people. Afterward, Gordon tells Bullock inside his office that they needed to bring in Strange. However, as acting captain Bullock told Gordon that he couldn't without a charge, as the entire city had him under a microscope. While leaving, Gordon crosses paths with Bruce who informs him that Professor Strange had Selina Kyle. Elsewhere, a white-haired woman watched Bullock explain Azrael's death on the news. She then used a phone to tell a man that Strange was losing control, and that they needed to gather The Court.
Elsewhere in Indian Hill, Hugo Strange and Ms. 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, Ms. Peabody warns Strange that their employers were going to shut them down. However, Strange is not deterred as you couldn't order scientific discoveries. He then decided to try to resurrect "Patient 13".
At Wayne Manor, Alfred berates Bruce for involving Selina, who was now in danger because of him. However, Gordon and Lucius Fox decides to use this opportunity to infiltrate Arkham Asylum and find the secret laboratory where Hugo Strange was creating monsters. Given that, and despite Alfred's protest, Bruce decides to accompany Lucius announcing that he'd ask for a tour as the Wayne foundation gave money to the Asylum every year. Meanwhile at Indian Hill, Strange prepares to revive Fish Mooney after combining her DNA with cuttlefish DNA. Above at Arkham Asylum, 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. Back in Indian Hill, Fish Mooney is successfully resurrected. At Wayne Manor, Bruce and Alfred part ways, and Alfred gives Bruce his blessing to go, telling him that Thomas Wayne fought very hard for what he believed in, and he wouldn't stop Bruce for doing the same thing. Meanwhile at Indian Hill, Fish Mooney comes out after changing her clothes. Strange attempts to see if she remembered her previous identity, though after she says nothing he attempts to give her a persona. However, Fish rejects the persona as she knew who she was, then demanded that Strange tell her what was going on.
At Arkham Asylum, Hugo and Ms. Peabody watched Fish Mooney in her cell from a security monitor in Strange's office. 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 Edward Nygma's offer, and he told her that he'd let Nygma take a shot, as he was clever enough to find his way to the basement. She then informed Professor Strange that Bruce Wayne was outside of Arkham asking for him. Professor Strange told Ms. Peabody that he wanted to talk to Bruce, and then remarked that he was impressed by him.
Outside, Strange meets with Bruce and Lucius, and Bruce asks for a tour, using the fact that he supplied the Asylum with a quarter of their operation budget to get one. He then told Strange that he wanted to talk with him, while Lucius look around, and although Strange told him that Lucius couldn't wander by himself, he offered Ms. Peabody as his guide. Lucius then agreed, and using the excuse of going to get his coat, let Gordon out the trunk in his car, telling him that if he saw anything suspicious he would mark it with white chalk. Gordon then entered the Asylum disguised as a security guard. Elsewhere in the Asylum, Ms. Peabody gave Lucius a tour of the facility, and Lucius activated his Geiger counter that he had designed to find the location of the Indian Hill facility.
In Strange's office, Hugo confronted Bruce about the real reason he was there. The conversation eventually shifted to murder of Bruce's parents, and Bruce and Hugo both agreed that there was someone to blame for the killing. Meanwhile, Lucius continued his tour of the facility though Peabody catches him with the Geiger counter, however, he excuses it as device that measured the air quality. Soon after, Lucius finds the entrance to the Indian Hill facility using the device, and marks the wall with white chalk before continuing with Ms. Peabody. Back in Strange's office, Hugo and Bruce discuss Thomas Wayne, telling Bruce that Thomas' moral principles are what got him and Martha killed. Strange eventually asks Bruce whether he would trade his moral principles for one more day with parents. Bruce then accuses him of ordering his parents' murder. Hugo tried to warn him to turn back, and make the choice his father didn't. Elsewhere in the building, Gordon finds the marking Lucius left on the wall indicating that it was the entrance to the Indian Hill facility.
In Strange's office, Hugo told Bruce that Thomas' actions were what killed him and Martha. Strange pleaded with Bruce not to follow his father's path, though after Bruce made it clear that he would do the same as his father, Strange orders that Bruce, Gordon, and Lucius be taken. Several orderlies confronted each of them in separate parts of the building, and before Bruce was taken out of his office, Strange told Bruce that he was truly his father's son, and that he respected that. As he was being taken out of the office, Bruce demanded to know what Strange had done to Selina Kyle. Down in the Indian Hill facility, Selina uses the flamethrower to try to open the door, but repeatedly fails. At that time Bridgit regains consciousness. Elsewhere, Fish Mooney asks an orderly bringing her lunch about her whereabouts. After he tells her nothing, she grabs his hand and orders him to make her a grilled cheese sandwich. In Strange's office, he watches Bruce, and Gordon on his security monitors. While doing so, Strange is confronted by The White-Haired Woman, who questions his progression on his ordered objective of bring back the dead with their memories intact. Although she states that he has failed at his mission, Strange brings up his recent success with Fish Mooney, and is then ordered to move everything to the facility upstate and destroy Indian Hill with the explosive device.
Back in her cell, Fish is brought a grilled cheese sandwich by the orderly she ordered to do so. When questioning him as to why, he told her he didn't know, only that she had told him to. After he left, she looked at her hand in bewilderment. Elsewhere, Bridgit regains consciousness and takes another flamethrower to kill her friend, but Selina's pleas make her remember killing her brothers, thought this only furthers her determination to kill her. After being forced to shoot Bridgit with the flamethrower, Selina is surprised to find out that Bridgit couldn't be hurt by fire. However, Selina manages to save her life by convincing Bridgit that Strange had sent to her be her servant. At the GCPD, Alfred informs Bullock that Bruce, Gordon, and Lucius were still inside Arkham. Bullock then orders several GCPD officers to Arkham to go and get the trio. Meanwhile, Lucius and Bruce are locked in a room, where from the control room outside, Nygma announces his presence. Meanwhile, Gordon is brought to one of the laboratories in Indian Hill where Strange has a helmet placed on his head, and solution poured in.
Nygma told Bruce and Lucius that Strange had tasked him with finding out how much they knew about what Strange had been up to, and who they had told. He then informed them that if they didn't, poison gas would spill from the nozzles above their head, and kill them. Lucius was then able to identify Nygma through his voice, and Nygma gave them five minutes on a timer to answer before the gas was activated. Back in Indian Hill, Strange removed the helmet and comes face to face with Basil. The helmet was then put on Basil, and elsewhere in the city, the GCPD made their way to Arkham. Lucius and Bruce banged on the door for help, Selina brought Firefly her flamethrower, and after the helmet was taken off of Basil. Jim was surprised to see Basil had a face identical to his, and Strange then put a wig on him so he looked identical to Gordon. Basil then mimicked Gordon, to Gordon's horror.
- Fish Mooney's hairstyle in this episode creates a minor continuity error. The hair on the sides of her head was shaved off when she died in "All Happy Families Are Alike" and her corpse seen in "Rise of the Villains: Worse Than A Crime" still had the same haircut. However, the hair has noticeably regrown in "A Legion of Horribles", even though she spent the last year in stasis, meaning nothing should have changed about her hair.
- Robin Lord Taylor (Oswald Cobblepot) does not appear in this episode, the third of five in which he is absent.