Breaking Bad creator Vince Gilligan and actor Bryan Cranston addressed the combined universe theory at a special San Diego Comic-Con panel to mark the show's 10th anniversary.
"Walt is dead, so he could be a zombie right now," Cranston pointed out. "Heisenberg zombie! My agents are out here, we should talk."
The theory of a combined Walking Dead-Breaking Bad universe has been around for years, and was so prominent that College Humor even made a mash-up trailer in 2013. The idea is that Walter White (Crasnton) made a bad batch of them, which led to the zombie outbreak we see in The Walking Dead and Fear the Walking Dead.
Fear's third season even included a Breaking Bad Easter egg, when the song "Negro y Azul: The Ballad of Heisenberg" was heard. Viewers also noticed that Merle Dixon was seen with a collection of blue drugs, which resembled Walter's Blue Sky meth, in The Walking Dead's second season. Darryl's description of Merle's drug dealer also matches Jesse Pinkman, Aaron Paul's Breaking Bad character.
Walking Dead creator Robert Kirkman also jokingly confirmed the theory during a Walker Stalker Cruise in February. He told one fan, "I'll confirm that theory, sure."
During the panel at Comic-Con, Cranston also told fans he does not think Breaking Bad should come back, five years after it ended.
"We're very proud of our show and Better Call Saul. In some ways, it's best to leave it alone – that you want to think back on it favorably," Cranston said Thursday. "I don't want to mess with it. It was the perfect opportunity that changed all of our lives. It changed many lives on our show."
However, Gilligan teased possible spinoffs with other characters, including Jesse. More characters could also pop up in Better Call Saul, although Walter and Jesse are not in the cards for season four.
The new episodes of Better Call Saul begin airing on AMC Monday, Aug. 6 at 9 p.m. ET.