Spoiler alert! Do not proceed if you have not watched Netflix's Firefly Lane.
Kate and Tully's 30-year friendship seemed like it'd be unbreakable, but by the finale of Netflix's Firefly Lane, the two BFFs were no longer on speaking terms in the closing flash-forward at the funeral service for Kate's father. What happened between the two friends that caused such a dramatic rift -- to the point where they were forced to (or worse yet, chose to) sever ties?
"We need a season 2 because it ends on that cliffhanger," Sarah Chalke, who plays Kate, told ET's Katie Krause of the unsettling ending. "You see them go through so much and they get through it because at the end of the day, they're just there for each other. They're family. So it's got to be something big."
Katherine Heigl, who plays Tully, expressed optimism that it couldn't be solely because of Tully and Johnny's romantic affair, which caused some tension between the tight-knit friend group. (Johnny, played by Ben Lawson, is intertwined with the two women as their boss and later, Kate's husband.) "It cannot be that Tully sleeps with Johnny after they're married," she said. "I don't think any friendship comes back from that." Heigl theorized it's more likely to have something connected to Kate's young daughter, Marah (Yael Yurman).
As creator and showrunner Maggie Friedman hinted to ET in a separate interview, she has the answers to that looming question. "I know what it is and I have a plan," she promised. "I hope that people watch the show and that we get a season 2. That's up to Netflix. But I have a lot of exciting ideas for a season 2 should we be so lucky. So I hope we do."
"One of the beautiful things I will say about this story, and one of the reasons I love it, is that even though there is a love triangle, their relationship is bigger than that," Friedman said of whether Kate and Tully's fallout is over Johnny. "Their sisterhood is stronger than any man could come between them. And they are soulmates. I think that's cool because there's a way that story could've been told where it's all about Johnny and them cat-fighting over Johnny. But that's not what it is at all. I feel sympathy for both of them when they're grappling with their different feelings for him. In episode 7, when Tully sleeps with Johnny, it's a real test for their relationship... and hopefully you're on everybody's side. Ultimately, their friendship matters way more than any guy."
Though Kate and Tully's friendship is no more in the near future, Johnny's fate also remains uncertain. After he goes off to Iraq to cover the war (not before having one last goodbye hookup with Kate, who's still in love with him), the group he is embedded with falls victim to a large explosion. It's unclear if Johnny survived the blast or was severely injured as a result.
"I think you're made to wonder if he's OK and I think that all things going well, we're going to see him more often and not just in flashbacks," Lawson hinted. "There's a lot unresolved between Kate and Johnny as well. Gotta get him back home safe." Friedman said Johnny's fate and what happened would be a "reveal" that'd take place in a potential season 2.
"I have hope for them," Lawson said of Kate and Johnny's complicated relationship status. "I think for them, I don't know where Johnny is without Kate. She's sort of given meaning to his life where previously he would have drifted through life as a rolling stone and a lone wolf. I think he needs her and I would like to see him grow up. I think he still has some growing up to do and get this thing out of his system and really find a deep happiness. I would like to see him find real happiness with him and his wife."
"I think Johnny is the love of her life," Friedman agreed. "In episode 10, before he leaves, they both really realize that. And they get to have a little time together. I think that's because they both still love each other."
As for Tully's romantic life, whose relationship with EMT Max (Jon Ecker) appeared to end, Heigl remained hopeful they could rekindle their romance.
"Jon is such an incredible actor and he was so beautiful in that role, so I'm really hoping," she praised. "He is the first guy that Tully has been really in love with for years. Since Chad. He can't go away, that would be awful." "I'm just rooting for them so much. They're so good together," Chalke chimed in.
"The two of them are so great together and you feel like they really love each other. I think he's amazing -- Jon Ecker, the actor -- and they're so good together that I would never say never to that because I really enjoy them as a couple. I'm rooting for them too even as I'm deciding who's not showing up at that gazebo. I'm still rooting for them," Friedman said. "She really hurt him. She broke his heart. At that moment, he's not ready to be vulnerable again with her because he feels like he is the one that keeps getting hurt."
Firefly Laneis now streaming on Netflix. For more on the series, watch below.