Here's what to expect on tonight's episode of 'Yellowstone'

• Season five, episode six of "Yellowstone," airs Sunday.
• The preview shows an unexpected accident during the Duttons' cattle branding trip.
• Here's a frame-by-frame breakdown of the preview for the episode.

Sunday night's episode of "Yellowstone" teases a tragedy on the Duttons' cattle branding trip.

The preview for episode six, titled "Cigarettes, Whiskey, a Meadow and Fog," begins with John Dutton (Kevin Costner) sharing a private moment with his youngest son, Kayce (Luke Grimes).

"We can sell it, son. We can bottle it up and sell it," John says looking around and taking in the breathtaking beauty of the Montana mountains.

Beth (Kelly Reilly) is similarly feeling sentimental. The trailer cuts to her and her husband Rip (Cole Hauser) riding through a forested area, before dismounting and sitting down for a chat.

"I could live here and never see another person in my whole life except you," she sweetly tells him as he gazes at her adoringly.

Back at the ranch, Summer (Piper Perabo) is seen heeding Beth's advice and exploring the Dutton land. We see her come across the family cemetery where some of the graves date back to the latter half of the 19th century. We see closeups of some of the headstones, including a weathered one bearing the name Margaret Dutton, a name that will be familiar to viewers of the spinoff prequel series "1883."

However, the camera lingers on another that is in far better shape, suggesting it belongs to a Dutton descendant that passed not as long ago. The name on the grave is Patience Dutton, a deceased family member viewers have yet to learn about.

Soaking in the long history of the ranch, Summer exclaims, "This family's been here that long," to which Monica (Kelsey Asbille), the only other person who has been left behind from the trip, responds: "When I say we give everything to this land…"

It's clear that Summer thought she was alone, and, upon hearing Monica's words, spins around, startled. The preview then cuts back to the cattle branding expedition where the cowboys are seen herding their errant livestock.

We then hear the end of Monica's sentence: "I do mean everything."

In quick succession, we get a shot of an air ambulance descending, John galloping with a concerned look on his face, and then the patriarch cradling someone in his arms. The person is sobbing into his shoulder, meaning their face is obscured but from their hairstyle, we suspect it could be either Tate (Brecken Merrill) or Carter (Finn Little).

John's assistant, Clara (Lilli Kay), appears, wordlessly taking in the scene before Beth and Rip arrive. Riding up to John, they ask: "What happened?"

We don't hear John's answer, but given that Beth — who is rattled by next to nothing — is then seen looking solemn and removing her hat in respect, we can assume it's something bad.

The preview closes with John desperately looking around, trying to find the words to articulate whatever horror he has witnessed.

"Yellowstone" airs Sundays at 8 p.m. on Paramount Network.