'Iron Fist' Season 2 Has a Great Reference to Earth-616

Iron Fist's second season is now available on Netflix and like every other Marvel television show, it's got some clever Easter eggs for viewers to find -- including a great reference to Earth-616.

Warning: spoilers for the second season of Iron Fist's second season beyond this point.

In the season's fifth episode, "Heart of the Dragon," Colleen Wing (Jessica Henwick) and Misty Knight (Simone Missick) go out looking for Danny Rand (Finn Jones), who is missing after what they think may have been an attack by Mary (Alice Eve). While they are driving around looking for leads, the police radio in Misty's car alerts all units of a "six-one-six". Colleen asks what that is, and Misty explains that it's police code for "possible subjects with abilities" (via Reddit).

For Marvel Comics fans, however, the reference goes a little deeper. In comics, each Earth within the multiverse has its own designation and Earth-616? Just so happens to be the main Earth meaning that all of the main Marvel comics take place within that world -- including the adventures of teams not (yet) represented in the Marvel Cinematic Universe such as the Fantastic Four and the X-Men. The designation was first used back in July 1983 in Alan Moore and Alan Davis' Marvel UK story "Rough Justice" as a way to differentiate Brian Braddock/Captain Britain from the other members of the Captain Britain Corps.

As the Marvel Cinematic Universe -- the world Iron Fist takes place in -- exists outside of Earth-616, the reference makes for a nice little nod for Marvel fans, but it might also be a reference that could subtly lay the groundwork for the X-Men. When the Walt Disney Company's acquisition of 20th Century Fox officially closes sometime mid-2019, Marvel Studios will be free to introduce mutants across the MCU should they so choose. While a Disney-developed X-Men film shouldn't be expected until around 2022 thanks to the current three-year turnaround time for Marvel Studios, television references could happen well before then and X-Men would definitely fit the bit as "possible subjects with abilities."

Did you catch the Earth-616 reference? Let us know in the comments below.

Iron Fist season two is now streaming on Netflix.