The Walking Deadincluded aBreaking BadEaster egg on its newest episode, but unless you were looking for it, you probably missed it. In the episode, the backstory was provided for Alpha, the leader of the sinister new group of flesh-wearing marauders called the Whisperers. As revealed in the show, Alpha used to sing a certain song with her husband Frank to their daughter, Lydia. Appropriately, the song was “Lydia, the Tattooed Lady.” OnBreaking Bad, there was also a character named Lydia, and diehard fans might remember that in the show’s series finale, Todd used the same song for her ringtone.

There have been multiple subtle references toBreaking Badon pastWalking Deadepisodes as well. Perhaps the most famous of these Easter eggs came in Season 2, when Daryl revealed his brother Merle’s stash of drugs had some of Walter White’s trademark blue meth inside. Daryl later told a story to Beth Grimes about a drug dealer who was described as a “janky little white guy,” who said to Daryl, “I’m gonna kill you, bitch.” That description sounds dead-on for Jesse Pinkman, floating that idea that the man Daryl was referring to and Jesse were one in the same. Could it even be that, somehow, Walter’s special blend of meth eventually resulted in the zombie apocalypse seen inThe Walking Dead?

Of course,Breaking Badis far from the only other franchise to be recognized byEaster eggs on The Walking Dead. Many iconic zombie movies and horror films have also had on-screen tributes make it into the series. Notable zombies from classic George A. Romero movies likeDawn of the DeadandDay of the Deadhave had “cameos” on the show, looking exactly as they did in the movies. The crate from a segment in the originalCreepshowmovie is also shown hidden away in the foreground of a scene.Walking DeadEP Greg Nicotero had visited theCreepshowset during production, and is now spearheading a TV series based on the movie for Shudder, so it seems likely that particular Easter egg was his work.

Season 9 ofThe Walking Deadhas been very well received with fans and critics, despite the show’s overall falling ratings.New showrunner Angela Kangcame on board at the start of the season to replace Scott M. Gimple, and the quality of the series has seen an upswing under her watch. Unfortunately, with several major players like Andrew Lincoln, Chandler Riggs, and Lauren Cohan leaving the series, trying to restore fan interest could be an uphill battle. It certainly doesn’t help matters that Danai Gurira has decided to end her run as Michonne on the show as well.

Breaking Badis in the midst of having an official sequel movie made, continuing the story established by the show.Aaron Paulwill reprise the role of Jesse Pinkman for the movie, and it seems likely Bryan Cranston will have some sort of cameo in a flashback scene. For more ofThe Walking Dead, you can catch new episodes when they air Sunday nights onAMC.