Katherine Heigl and Sarah Chalke Are Best Friends Forever in Netflix's 'Firefly Lane' Trailer (Exclusive)

ET exclusively premieres the official trailer for the upcoming drama series.

In Netflix's new drama series, Firefly Lane, Katherine Heigl and Sarah Chalke play best friends whose powerful bond stands the test of time -- 30 years, to be specific -- and only ET has the exclusive first look at the official decades-spanning trailer. 

Adapted from Kristin Hannah's novel, unlikely duo Tully (Heigl) and Kate (Chalke) meet when they're both 14 years old and they can’t be any more different. While Tully is brash and bold, Kate is the shy girl you never notice. But when a tragedy brings them together, they're bonded for life and inseparable best friends. Together, they experience 30 years of ups and downs -- triumphs and disappointments, heartbreak and joy and a love triangle that threatens their friendship.

As Tully goes on to experience wealth and fame, Kate chooses marriage and motherhood. But through it all, their friendship remains intact, until they're faced with the ultimate test. 

"You don't get it. You don't know what it's like to fail. You succeed at everything you try," Kate opens up to Tully, as we see her sliding off her wedding ring in the trailer. "It's like this is your life and I'm along for the ride."

"You are so much braver than me," Tully assures her BFF. "Your family? That is the real accomplishment. I will never have that. I was too scared to even try."

Joining Heigl and Chalke in the cast are Ben Lawson as Johnny, the man at the center of the love triangle; Ali Skovbye as young Tully; Roan Curtis as young Kate; Yael Yurman as Marah; and Beau Garrett as Cloud.

Hannah serves as an executive producer, alongside creator and showrunner Maggie Friedman, Peter O’Fallon, Heigl, Shawn Williamson and Lee Rose.

Firefly Lane drops Wednesday, Feb. 3 on Netflix.

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