Netflix's latest hit series, Firefly Lane, stars Katherine Heigl (Suits) and Sarah Chalke (Speechless) as two adult BFFs whose 30-year friendship is — unbeknownst to them — coming to its end. Based on Kristin Hannah's 2008 novel of the same name, the series only covers the first half of the book, leaving viewers to wonder what happens in the Firefly Lane book ending. The novel is an infamous tearjerker, but you know you'll love every minute of it. Spoilers for Firefly Lane follow.
Firefly Lane opens in 1974, when social outcast Kate Mularkey (Chalke) meets Tully Hart: cool-girl extraordinaire (Heigl). By the end of the summer, the two have become an inseparable unit, known as "TullyandKate." They remain right by one another's sides for the next 30 years, until a major betrayal puts an end to their friendship — seemingly for good. Years later, a second tragedy brings Tully and Kate back together again, but by that point they have very little time left to spend with one another.
Even though they're BFFs, Kate and Tully live very different lives. Tully's an attachment-less career journalist and the host of a popular daytime talk show, The Girlfriend Hour. Meanwhile, Kate is married to Johnny — an old fling of Tully's — and works a stay-at-home-mom to her teenage daughter, Marah, and younger twin boys, William and Lucas. Their differences put a strain on their relationship at various points in Hannah's novel, but when a well-meaning Tully ambushes Kate with a heavy-handed criticism of her parenting style — during a live broadcast of The Girlfriend Hour — Kate ends their friendship immediately.
A few years later, Tully returns from working on location in Antarctica to find a voicemail from Kate: "Hey, Tul. It's me. Kate. I can't believe you haven't called to apologize to me." Offended by the idea that her ex-BFF has called to wrest an apology from her, Tully ignores the message for months, until she takes a second call telling her the awful truth. Not only has Kate been diagnosed with Stage IV inflammatory breast cancer, but she's also undergone every treatment available to her. The cancer has metastasized to her brain, and she doesn't have much time left.
With Kate on her deathbed, she and Tully make amends. They pick their friendship up right where it left off, but their bond cannot save Kate from the inevitable. She asks Tully to watch over Johnny, Marah, William, and Lucas, and dies shortly afterward, as the novel comes to its close.
If you're thinking, Well, that wasn't in the show!, you can rest easy knowing that Netflix's Firefly Lane only covers the first half of Hannah's novel. The series hasn't been renewed at the time of this writing, but there's still plenty of Firefly Lane left to adapt, when and if Netflix wants to do so.
Netflix's Firefly Lane is streaming now.