'Firefly Lane' Ending Explained: What Did Tully Do?

Firefly Lane on Netflix details the decades-long friendship of Tully Hart (played by Katherine Heigl) and Kate Mularkey (Sarah Chalke), but by the end of the current season they are no longer friends. In a scene towards the ending of Episode 10, the pair are together at Kate's father's funeral, and we learn that the pair no longer speak to each other. The show, however, does not tell viewers why.

What did Tully do in Firefly Lane?

The Netflix show seems to hint that their falling out may be something to do with Johnny (Ben Lawson). In the final episode "Auld Lang Syne", the funeral scene follows one in which Johnny's squad sets off a mine in Iraq.

Viewers do not learn whether Johnny died or not there, but if he did, this could have put a wedge between them. If he died, perhaps Tully did not tell Kate for whatever reason, or if he is still alive, perhaps Tully and him slept together in a fit of relief that he was still alive.

In an interview with Oprah Magazine, Heigl said that she will, "fight to the death" to stop any plotline that would see Tully betray Kate by sleeping with Johnny. She added, "It cannot be that Tully sleeps with Johnny. I don't think any friendship would come back from that."

firefly lane what did tully do
'Firefly Lane' on Netflix ends with Kate (played by Sarah Chalke, left) and Tully (Katherine Heigl, right) having fallen out. Netflix

Sarah Chalke, meanwhile, spoke about what Tully did in an interview with The Wrap. In this interview, the former Roseanne actor said: "I don't even know, to be 100% honest, what the actual last straw is. I know what it is in the book, but I don't know if Maggie [Friedman, showrunner] will choose to use that or something else, if we're lucky enough to get to continue for another season."

If the series follows the book, then the pair fall out after Tully interviews Kate on her TV show and basically humiliates her on live television. Like in the Netflix show, Kate has problems in the book with her teenage daughter Marah (Yael Yurman), and Tully invites her on The Girlfriend Hour to discuss these issues.

Though she might mean well, what Tully does is insinuate that Kate is a terrible mother. The segment is about "overprotective mothers and the teenage daughters who hate them," and a psychologist criticizes mothers like Kate for being, "controlling, domineering mothers" who "damage their children's fragile psyches."

In her Oprah Mag interview, however, Heigl hinted that the show may change this plot point as the showrunner is not convinced it is a "strong enough" reason for such firm friends to stop talking. The Grey's Anatomy actor, however, said of the book's plot, "that would be enough to put a serious rift in the friendship."

Showrunner Maggie Friedman, meanwhile, told Entertainment Weekly: "I don't want to say whether it's directly the same thing...One of the things I think that's been fun is that we have kept some big moments from the book and been very true to those, and then there are other things that we've done that are different."

Firefly Lane is streaming now on Netflix.