This post contains spoilers for Little House on the Prairie.

“The Ingalls are coming, hurrah, hurrah! The Ingalls are coming to Kansas now!”

These joyous lines of song help kick off Netflix’s fresh new take on Laura Ingalls Wilder’s classic novels of pioneer girlhood, Little House on the Prairie.

Helmed by The Boys producer and The Housemaid screenwriter Rebecca Sonnenshine, the new series diverges in significant ways from the classic TV drama, which ran on NBC from 1974 to 1983. The Netflix production adapts the books only, not the original show. But there are certain scenes so central to little Laura’s journey that they demanded inclusion on both shows.

Case in point: The Ingalls family’s perilous river forge as they make their way from the Wisconsin woods to the open prairies of Kansas. Alice Halsey and Skywalker Hughes, who play sisters Laura and Mary Ingalls, lull viewers of the new series’ premiere into a deceptive calm with their folksy balladeering. But within minutes of the episode’s start, the Ingalls come face to face with their first big hurtle en route to that little house — and it isn’t easily cleared.

Sonnenshine sat down with Entertainment Weekly ahead of Thursday’s Little House on the Prairie premiere to break down what went into keeping everyone safe — horses, dogs, and people alike —when shooting such a challenging scene.

“That was an incredible mixture of all sorts of things — water work, horses, incredible performances in a challenging situation,” she says. “Our director, Sarah Adina Smith (Birds of Paradise, Buster’s Mal Heart), she did such a great job of conceiving all of that, and really, I think it’s important to have a really good performances while you’re doing all that. So that is really what we were trying to focus on.”

Though packed with action, the first five minutes of Little House on the Prairie are indeed driven by the core cast’s impassioned performances. Luke Bracey (Elvis) steps confidently into the massive shoes left by Michael Landon, who played Charles “Pa” Ingalls on the original series, in addition to directing many episodes and steering the show creatively. Crosby Fitzgerald takes over as Caroline “Ma” Ingalls from O.G. star Karen Grassle, while Halsey and Hughes’ Laura and Mary are roles made famous by Melissa Gilbert and Melissa Sue Anderson, respectively.

But Smith’s direction of the pilot’s opening scenes also drives home the series’ tone, which turns on a dime between pastoral quietude and thrilling action. Laura and Mary, in fact, sing their song as the family traverses a cliffside overlooking the very river that moments later they’re forced to cross.

“It’s a very complicated sequence, in terms of keeping everybody safe, the horse safe, our actors safe, and conveying this incredible danger, which is symbolic of a point of no return, right?” Sonnenshine explains. “Once they get past that river, they can’t go back. Can you imagine crossing that again?”

The Ingalls are thoroughly disabused of any notion they might turn back to Wisconsin when the river forge nearly ends in disaster. As in the the original Little House pilot, Laura sweetly asks Pa if the family dog, Jack, can cross with the family ensconced in the safety of their covered wagon, rather than braving it alone like the horses before the cart. In both shows he assents, and in both, Jack leaps out of the wagon mid-crossing.

In the new Little House, the wagon buckles and dips, as Pa finds himself submerged up to his chin in coursing water. A wheel is caught on a heavy, submerged stone, and the horses begin to panic when they get stuck because of it. A blink-and-you’ll-miss it shot of Caroline holding fast the reins shows the effort has left her palms bloody. The girls scream, Jack floats down river, and viewers ask themselves, “How did they shoot this safely?”

“It was a super, super complicated sequence. But it all came together,” Sonnenshine says. “We had an incredible VFX team, and incredible, special effects team, and we just love everybody we work with so much.”

When pressed, Sonnenshine breaks down the specifics of the scene which is rendered in such a way that it appears entirely shot on location.

“It’s shot in a tank. Everything is separate because you can’t have horses with actors in the same spots,” she explains. “So everything is shot in a giant tank and then other things are shot on location. Then it’s all kind of melded together into this really fun and exciting sequence that also has an incredible soundtrack. That really helps sell it.”

The Ingalls eventually make it to the other bank, and then to their new home in Kansas. And — spoiler alert to spare readers who haven’t seen the premiere a fretful visit to doesthedogdie.com — Jack survives, reuniting with the family as they build their little house.

Entertainment Weekly previewed Sonnenshine’s new vision of the out West classics back in May.

She cautioned that super-fans of the original series shouldn’t expect a beat-for-beat remake. Her Little House on the Prairie is squarely focused on Ingalls Wilder’s coming-of-age tales, which published between 1872 and 1894.

That said, “the spirit of the [original] show is going to overlap. We’re also using a little bit of the history of Laura Ingalls Wilder’s real life, which the show did as well,” Sonnenshine explains. “And there are things we incorporated in the show that are from outside the books, that were part of her life, or a part of history at that time.”

Ingalls Wilder’s approach to Little House on the Prairie was all about “finding a way to expand on some of those stories and some of those characters to create something that felt very much like modern television,” Sonnenshine says.

Little House on the Prairie is currently streaming in its entirety on Netflix.