Katherine Heigl and Sarah Chalke as 20-year-old Tully and Kate in Netflix's "Firefly Lane."

Katherine Heigl and Sarah Chalke as 20-year-old Tully and Kate in Netflix’s “Firefly Lane.”

Image: COURTESY OF NETFLIX

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It goes without saying yet still needs to be said: Not every book needs to be adapted for TV or movies. For producers ignoring this warning and moving ahead anyway, you have one job: Tell us why. Why this story, this moment, this medium of storytelling? Why these creative liberties — or lackthereof?

Netflix’s Firefly Lane, based on the novel by Kristin Hannah, is a show that fails to answer any of these questions. It tells the story of best friends Kate (Sarah Chalke) and Tully (Katherine Heigl), who have known each other since eighth grade and remain enmeshed in a tight-knit, volatile, and sometimes unhealthy relationship 30 years later.

Their story is told over three timelines: The ’70s, the ’80s, and 2003, with the girls aged 14, early 20s, and 43, respectively. Because Chalke and Heigl inexplicably play their 20-year-old selves and the ghost of this creative decision hovers over the entire series, we need to discuss it up front. There is some light de-aging and a cute color filter on the ’80s scenes, but we simply do not have the technology to make people in their 40s look 20 years younger. AND THAT’S OKAY. I would have loved to see these 2000s TV darlings owning it as two grown adult women negotiating their mature dynamic. Teen Kate and Tully are portrayed by different actors (Roan Curtis and Ali Skovby, respectively), so why not cast them as the young adults who are just SIX years older? It gets especially fun when 38-year-old Beau Garrett plays mother to 43-year-old Heigl as a 22-year-old. And by fun I mean gaslighting the audience.

14 going on 40

14 going on 40

Image: COURTESY OF NETFLIX

Then there’s the timelines themselves, which are muddled from the outset by those shared actors in distracting wigs. The show gains absolutely nothing from sticking to Hannah’s timeline, adding insult by not committing to the…unique sartorial aesthetic of 2003. Where are the low-rise bellbottoms, the t-shirts over long sleeves, the weird fringe belts, the ponchos? Maybe these two were old enough to know better, but don’t tell me Kate’s 29-year-old boss was rocking beach waves in a time when the very air reeked of straightener-burn for the better part of a decade. SHOW IT TO ME. COMMIT.

The reason for this timeline is, ostensibly, a man: Johnny Ryan (Ben Lawson + another horrendous wig), Tully’s TV producer who is also Kate’s separated husband, father of her child, and the man she fell in love with the moment she laid eyes on him in ’82. He reports on the Salvadoran Civil War in 1984 and goes to Iraq in 2003, both of which get a few sentences of exposition but feel incredibly forced. No period of time is lacking in war or trauma that these two events had to anchor the entire show. Johnny even has PTSD from El Salvador, but the entire experience and his character-focused episode come so late in the game that it just does not land. The same happens with Kate’s brother Sean (Jason McKinnon) because their stories are concentrated, across multiple timelines, into specific episodes — rather than told linearly as in the book.

Hannah’s novel must have something special to get adapted in the first place, that took over a decade after publication, but it gets lost in translation for TV. It’s unclear whether this is a weakness of the original text or the adaptation, which doesn’t even take on the whole book. Key events remain unexplained even after 10 episodes, and the introduction of a fourth timeline, 2005. If I want to be yanked through time by emotional upheaval, I’ll watch This Is Us, which at least has better age makeup and wig resources.

Ultimately, the on-screen versions of Kate and Tully fail to spark any real feeling. I want Kate to be more assertive, to fight for what she wants and get it. I want Tully to stop self destructing. I recognize parts of myself and my girlfriends and our relationships in these women, but it’s all surface level. Mostly I want them to get a little space from each other. There is a deep, sisterly love here, but also an unhealthy mixing of personal, professional. The grown ups sound like teens because these relationships stunted their emotional growth. It’s nothing we haven’t seen before — but other versions of this story have an emotional resonance that Firefly Lane never gives.

Firefly Lane is now streaming on Netflix.