WARNING: The following contains major spoilers for "Pilot," the series premiere of Superman & Lois, which aired Tuesday on The CW.
The premiere episode of Superman and Lois is packed with Easter eggs and references to the comics and the history of the Man of Steel. In fact, the episode includes nods to the superhero's creators, Jerry Siegel and Joe Shuster, as well as Superman: The Movie director Richard Donner. There's even an amazing Golden Age homage that features Superman in the Fleischer cartoon series costume, recreating the cover of Action Comics #1.
The episode doesn't stop there, however, as the pilot also includes a reference to another important comic book location: Gotham City's Ace Chemical.
At the start of "Pilot," the show picks up with Clark Kent and Lois Lane, who are married and balancing their lives as journalists, parents and superheroes. While visiting the office of the Daily Planet, several televisions broadcast the heroic antics of Superman. On one of these screens, fans can see the Man of Steel fly over a disaster at a chemical plant, which just happens to be Gotham City's Ace Chemical.
Ace Chemical is an infamous location in the history of DC Comics. It's the place where the Joker was born, and a location that has been brought to life in various television series, video games and movies over the years, including 2016's Suicide Squad.
The scene is incredibly brief, but it shows Superman rushing to help the rescue efforts at Ace Chemical. While the episode makes no direct references to the larger Arrowverse, Superman and Lois is set in the shared universe that includes The Flash, Batwoman, DC's Legends of Tomorrow, Supergirl and Black Lightning. On Batwoman, it was revealed that Bruce Wayne has been missing for years, which means Batman hasn't operated as the city's protector for some time.
Given his absence, this brief footage implies that Superman is helping keep Gotham City safe. Even if there is now a Batwoman active in Gotham, the red-caped crusader operates primarily at night, and in the footage, the fire at Ace Chemical is clearly raging on during the day. Thankfully, Superman can travel to Gotham in a flash, to assist where he's needed, no matter the time of day. For now, it's just an Easter egg, but this could be a hint that, later on in the season, Superman and Lois could take the titular couple and their sons Jordan and Jon on a proper trip to Gotham City.
Superman & Lois stars Tyler Hoechlin, Elizabeth Tulloch, Dylan Walsh, Alex Garfin, Jordan Elsass, Emmanuelle Chriqui, Inde Navarrette and Wolé Parks. The series airs Tuesdays at 9 p.m. ET on The CW.