|01 "Year Zero"||07 "Ace Chemicals"|
|02 "Trespassers"||08 "Nothing's Shocking"|
|03 "Penguin, Our Hero"||09 "The Trial of Jim Gordon"|
|04 "Ruin"||10 "I Am Bane"|
|05 "Pena Dura"||11 "They Did What?"|
|06 "13 Stitches"||12 "The Beginning..."|
- "I know you're all asking, "Why are we still here when our own government wont help us?" Simple. We're supposed to giving these people hope. Hope that if they're in danger, someone will come. We will come. Suit up!"
- —Jim Gordon[src]
Jim Gordon and Bruce Wayne face the chaos Gotham City has become. Their mission to keep the city safe becomes more complicated, as the villains who survived the attack on the city begin to resurface and claim various territories. Meanwhile, Selina Kyle grapples with how to deal with her uncertain future.
Gotham is declared off-limits from the mainland by the government, allowing the city's criminals to gain numerous territories of the city whilst Gordon and the remaining GCPD officers gather refugees into the precinct for safety, though they soon begin to run out of supplies. In his transmission to the other side, he mentions that there are still innocent lives trapped in Gotham City while mentioning the territories claimed by Cobblepot (who claimed Gotham City Hall), Barbara Kean and the Sirens (who claimed the areas around their nightclub), and Scarecrow (who occupied Otisburg) while Victor Fries and Bridgit Pike are in a turf war and Jeremiah Valeska has not been sighted.
Bruce Wayne and Gordon begin to work together to rid the city of crime while Cobblepot begins to sell faulty ammunition around the city. Afterwards, the Scarecrow and his Scarecrow Gang steal their food and medicine, forcing Bruce to have Wayne Enterprises illegally fly supplies into the city.
Meanwhile, Nygma begins suffering from schizophrenic outbursts after he continuously blacks out and ends up in different locations upon waking up.
Simultaneously, Selina Kyle is operated on to prevent her spine from collapsing, though she remains paralyzed and she unsuccessfully attempts suicide; one of the hospital's doctors advises Bruce to seek out "The Witch" to save Selina.
Following a transmission from a woman stating to Gordon that he has allies on the other side of the river, he finds the map of the different criminal territories vandalized with a "Hahahaha" as he was unaware that Ecco snuck into Gotham City Police Department.
- We'll Meet Again - Vera Lynn
- Pure Filth - The Graves
- Hit Me - Levent
- Tanhauser - Act II Scene 4
- The title is a nod to Batman: Zero Year, which was a comic book event taking place in The New 52 / Rebirth continuity. It centered around Bruce Wayne's first year as Batman, during which the Riddler turned Gotham City into a wasteland and held it hostage, daring its residents to outsmart him.
- According to writer John Stephens, Season 5 will partially adapt Zero Year.
- The episode premiered on January 3, 2019.