|“||For months, I warned the police about the threats to our city, posed by Hugo Strange's freaks, by the murderer Fish Mooney, and how did they protect you? They said that Fish Mooney wasn't real, that these escapees were victims who need our help. Well, Fish Mooney was real, and once she was cornered by the GCPD, finally, they let her escape. And these "victims"-- well, I, for one, am not afraid to call them by their proper name: MONSTERS! Our city is invaded by monsters, attacking our brothers and sisters, and it is up to us! To you! To kill every monster you see! WHO IS WITH ME?!||„|
|~ Penguin encouraged Gotham City citizens to hunt down Indian Hill escapees dubbed the "Monsters".|
Former Arkham Asylum inmates, calling themselves "Monsters" due to the powers they obtained while being experimented on, are villains in the second and third season of the television show Gotham.
Secretly, Hugo Strange, the director of Arkham Asylum, is experimenting on various inmates of Arkham Asylum in a secret laboratory underneath Arkham, under the direct orders from the Court of Owls. There, he searches for a way to bring people back to death, which eventually succeeds when he brings back Theo Galavan, who he brainwashes into believing to be the ancient warrior Azrael. Realizing that the people he returned from death need a new identity in order to thrive, Strange begins creating new identities for the people he brings back. He also starts mixing the DNA of his experiments with other DNA, resulting in various powers obtained by the experiments.
However, the revived Fish Mooney, who has returned with her memories intact, highjacks a transporter supposed to deliver some of Strange's experiments to another facility. The truck crashes inside Gotham and the experiments are freed, venturing into the city on their own.
Six months later, most of these experiments have joined Fish's gang. The citizens of Gotham are horrified of the monsters inside their city and people, including former GCPD detective Jim Gordon, have started to hunt these monsters down for money. Oswald Cobblepot starts rallying the people of Gotham against the 'monsters', causing a city-wide hunt against them. Most of the monsters ended up fleeing or the city or killed by angry mobs. Oswald's war against the monsters earned him recognition from the Gotham citizens, which he used to secure his place as mayor of the city.
Ironically, Oswald would end up needing the help of the monsters when he himself was betrayed and banished from Gotham by his allies. This idea was suggested by Ivy Pepper, who had rescued Oswald following him being shot and dumped in a river by his former friend Edward Nygma. Oswald recruited two supervillains, Victor Fries/ Mr. Freeze and Bridgit Pike/ Firefly, the former of which was angry on seeing Oswald and strangled him due to being banished from the city, however agreed to a team up when Oswald said he would help Fries reverse his mutation once he takes back his power.
- Azrael: Formerly Theo Galavan, was the first person Strange successfully reanimated.
- Mr. Freeze: Formerly Victor Fries, was turned after commiting suicide with his freeze formula. Can only survive in sub-zero temperatures. Is later recruited by Oswald Cobblepot.
- Firefly: Formerly Bridgit Pike, was turned by Strange after having been horrifically burned. Turned into the 'fire-goddess' Firefly, but betrayed Strange after he threatened her friend Selina Kyle. Is later recruited by Oswald Cobblepot.
- Basil Karlo: Has the ability to shape-shift and change his voice. Used by Strange to impersonate Gordon but was arrested when he was revealed as a fraud.
- Fish Mooney: A former gangster, revived with her memories intact. As Strange fused her DNA with cuttlefish DNA, Fish has obtained the person to influence people by touching them, making them do whatever Fish orders them to do. However, the use of her powers slowly kills her.
- Marv: One of the experiments that was not turned by Strange but his assistant Peabody. Has the ability to age people by touching them, causing them to die of old age if he touches them long enough.
- Nancy: Skilled fighter, other abilities unknown. Wears a facial mask. Killed by an angry mob along with Sid while covering Fish Mooney's escape.
- Sid: Has the ability to run incredibly fast. Killed by an angry mob along with Nancy while covering Fish Mooney's escape.
- Tweaker: An agile man who has the ability to grow bat-like wings. Was arrested by Jim Gordon while attempting to kidnap Ethel Peabody.
- Ridgeback Monster: An incredibly strong but slow monster with ridges on his back. Fought Jim Gordon until he stumbled onto a street and was struck down by a truck.
- Skin-Burning Woman: An unnamed woman whose touch causes pain and burn marks on the body of the touched person. Last seen fighting GCPD officers in the old bank.
- Electrical Woman: A woman with the powers to create electricity from her hands. Last seen fighting GCPD officers in the old bank.
- Scale Skin Man: A man with a green skin and scales as well as reptilian eyes. Last seen fighting GCPD officers in the old bank.
- Jerome Valeska Doppelganger: Strange also seemed to have a clone of Jerome Valeska which escaped with the other monsters and may or may not become the feared supervillain "The Joker"
- Bearded Bulletproof Man: A bearded man seemingly impervious to bullets. Last seen fighting GCPD officers in the old bank.
- Two unnamed tall men
- An unnamed balding man
- An unnamed muscular man with a mouth guard.
- An unnamed man with a mangled hand.
- An unnamed man in a mask and goggles.
- An unnamed small person with head lumps.
- An unnamed snake-eyed person.
- Subject 514A: A mysterious boy, looks like Bruce Wayne albeit with long hair. His identity and agenda are currently unknown
- Karen Jennings: Was one of Strange's experiments when he ran Pinewood Farms. Her arm was turned into a reptilian arm with sharp claws. Died while defending Bruce Wayne against Mr. Freeze.
- Jerome Valeska: Was one of the dead people in Indian Hill. Instead of revived by Strange, the corpse of Jerome was later transferred into a warehouse owned by Wayne Enterprise, but later revived by Dwight Pollard and caused mass chaos in the city until Bruce and Gordon defeated him and made him locked up in Arkham Asylum.
- Alice Tetch: Has the ability to poison people if they get contacted with her blood, causing them to go mad. This poisoned disease can be spread by one victim to another.
- Despite being in different situations prior to entering Indian Hill, Karen Jennings, Fish Mooney, Victor Fries, Alice Tetch and Jerome Valeska were so far the only people among the monsters that had their memory intact after the experiment and/or resurrections upon them. Most of the monsters lost their memories after being revived and/or were later brainwashed by Strange.
- In a post on Cameron Monaghan's Twitter account in which he made reference to the fact anyone in the show could be the Joker (in reply to fans who were not happy that Jeremiah Valeska was possibly not the Joker), he acknowledged the Jerome look-alike from the end of season 2 and referred to him as a "hinted clone" and that he could be destined to become the Joker.