Kate Dies at the End of the 'Firefly Lane' Book, but What About in the Netflix Series?

Spoiler alert: This article contains spoiler for the Firefly Lane book and Netflix series.

Netflix's original drama series Firefly Lane is an absolute tearjerker with elements of mystery, heartache, love, and the bond of an unbreakable friendship.

Based on the novel by Kristin Hannah, Firefly Lane tells the story of the decades-long friendship between outgoing free spirit Tully Hart (Katherine Heigl) and introvert Kate Mularkey (Sarah Chalke).

The series, which only ran for two seasons, debuted on Netflix on Feb. 3, 2021, and dropped its final seven episodes (Season 2, Part 2) on April 27, 2023. In the book, Kate dies within the final pages — a tragic ending that absolutely nobody wanted.

Many fans have been wondering if Kate has the same fate in the Netflix series of if the plot would be revised for the sake of more seasons. Here's what we know.

Yes, Kate dies in the Netflix adaptation of Firefly Lane, as she loses her battle with breast cancer. While we love when a show stays true to the book, we were hoping that somehow the show's writers would surprise us with a different ending.

Throughout the series, Tully and Kate are inseparable; Kate and her family provide Tully with a sense of security as her own mother deals with substance abuse and her grandmother/caretaker passes away.

The two girls end up attending college together, and they both pursue broadcast journalism. (Tully is in front of the cameras, while Kate works behind the scenes.)

When both Kate and Tully develop feelings for Johnny Ryan (who is played by Ben Lawson), who also works at the news station, they deal with the first major hurdle in their friendship.

Kate ends up marrying Johnny, but not before he sleeps with Tully. 

While Kate decides to focus on her family, Tully remains uber career-oriented. She eventually gets her own daytime talk series, The Girlfriend Hour. Kate and Tully's different life paths cause some tension and jealousy.

Years later, Tully even becomes a friend to Kate and Johnny's daughter, Marah. She indulges Marah in a way that Kate doesn't agree with, and the relationship rubs Kate the wrong way.

Tully ultimately offers Kate the chance to discuss her parenting on an episode of her talk series, The Girlfriend Hour, but it ends up being an ambush to call Kate a bad mom.

After the taping, the two stop speaking.

Soon thereafter, Tully learns that Kate has breast cancer and that it's terminal. Despite thinking that they'd never reconcile their friendship, Tully and Kate reconnect during Kate's battle with cancer.

After writing Firefly Lane in 2008, Kristin Hannah followed it up five years later with Fly Away.

The plot of the sequel centers around Tully as she grapples with life after losing her best friend. It also features the continuation of Tully's bond with Marah, as she falls in love and mourns her mom's passing.

Tully's relationship with her mom, Dorothy Hart, is further featured in Fly Away as well. However, Netflix has already confirmed that Firefly Lane would only last two seasons, which means we'll probably never see Fly Away featured on screen.

Seasons 1 and 2 of Firefly Lane are now streaming on Netflix.