WARNING: This article contains major spoilers for "Romeo v Juliet: Dawn of Justness," the latest episode of DC's Legends of Tomorrow.
Supernatural isn't the only CW series that exists as a television show within the Arrowverse. In "Romeo v Juliet: Dawn of Justness," the latest episode of DC's Legends of Tomorrow, Nate Heywood confirmed Riverdale as well, with a shout out to the Archie Comics series.
In this episode, Nate was tasked with stopped a Shakespeare play they accidentally inspired. He discovered Shakespeare's actors rehearsing what appeared to be an Avengers: Infinity War-like play called Romeo v Juliet: Dawn of Justness. However, he was able to dismiss them with a simple proclamation: "Hear ye, hear ye! So there's been a change of plans. You guys have been replaced by Riverdale."
Riverdale is, of course, The CW's dark adaptation of the Archieverse. The show airs the day after Legends of Tomorrow and films nearby in Vancouver, Canada.
The Riverdale reference hit Legends of Tomorrow just one episode ahead of the team's visit to the Supernatrual set. Photos for "Zari, Not Zari," the next episode, show Sara, Constantine and Charlie hanging out with Baby, Supernatural's iconic Chevy Impala.
"In our world Supernatural is a TV show, not a real thing," co-showrunner Phil Klemmer explained after the photos emerged. That seems to be the case for Riverdale as well, given Nate's reference in "Romeo v Juliet: Dawn of Justness."
Airing Tuesdays at 9 p.m. ET/PT on The CW, DC’s Legends of Tomorrow stars Caity Lotz, Dominic Purcell, Brandon Routh, Nick Zano, Maisie Richardson-Sellers, Tala Ashe, Matt Ryan, Jes Macallan and Courtney Ford.