The Browns are going on their biggest adventure yet: a trip to the supermarket. In episode 9 of “Sister Wives,” fans will watch as Kody Brown and his family -- all 24 of them -- head to a Fred Meyer superstore to grab some grub.

“This has never, in my memory, ever been done before when we have, the entire family, four wives, dad, all of us, shopping for groceries,” the patriarch of the polygamist family says in a Season 6 sneak-peek video. “I don’t think we’ve ever done this once!”

Christine, Kody’s third sister wife, chimes in during a confessional, revealing that she doesn’t think a plural family -- let alone theirs -- has ever done something like this.

“This is a historic moment!” Kody giggles at the thought of his family swarming the aisles of the supermarket. 

According to the synopsis of episode 9, titled “A Boy or a Girl,” Kody and the gang will head to the grocery to stock their Alaska vacation home full of food while on their retreat.

The summary for the coming installment reveals that the Browns are heading for the Last Frontier. “They are all going to Alaska and they are bringing Logan’s new girlfriend, too," the synopsis says. In the sneak-peek clip, viewers watch the method behind the Browns’ madness as the TLC reality family food-preps for the week. “It’s organized chaos!” the summary teases.

“Twenty-four people times 24 meals -- because we’re here for eight days,” Kody says, wondering just how much food their crew will need.

“It’s 576 meals,” Janelle, the second sister wife, reveals the jaw-dropping number.

In the promo video, Robyn, the fourth sister wife, who is pregnant with Kody’s 18th child, explains how the sister wives divvy up the shopping list. While one preps for lunches, another covers the dinners and so on ...

“Each mom is in charge of getting certain things,” she says. “That way we’re not buying the same thing."

But as organized as the mothers are, Janelle notes that shopping with the large family is still a “challenging” experience. Fans of the TLC show can get a glimpse at the chaotic supermarket trip below:

“Sister Wives” airs Sunday nights at 9 p.m. EST on TLC.