We're digging into a video taken Thursday that shows tense moments on a very high and very fast section of the Gallatin River south of Bozeman.
The section of the river is a two mile stretch that runs below the highway bridge at Cascade Creek.
House Rock, at mile marker 62 on Highway 191, is one of trickiest spots on the river, and takes serious skill to navigate.
NBC Montana tracked down the man who shot the video, and spoke to a river rafting expert to learn who these rafters are, and what it's like to go down this section of the Gallatin River.
House Rock is an attraction this time of year. Bozeman resident Pete Sveen shot this video on Thursday.
"I got out my iPhone, and I shot a few minutes of video," Sveen said.
But, he didn't imagine he'd catch video of a raft tipping sideways and everyone falling into the rapids.
You won't catch Sveen out there.
"You have to be real experienced and have a good strong skill set to do that," he explained.
Turns out, workers at Montana Whitewater Raft Company knows the people in the raft. None of the people in the raft are from Montana Whitewater, but say they work for other rafting companies.
"The people you saw in that video are all professional guides," said Robert Price, a raft guide at Whitewater.
He explained this stretch of the river is especially dangerous at this time of year, because it is running almost twice as fast now as when Montana Whitewater takes out guided trips.
Right now, this area of the Gallatin River has class four rapids. It's not open for commercial use but experienced rafters said if you know what you're doing, this is exactly where you want to be.
"For your experienced boaters, this is the time of year... it's like the powder day of boating," he said.
Both Robert and Pete explained river rafting on the Gallatin is rewarding, if you know how to be safe.
"If they're not at the capability to go down in a raft or a kayak, do not go," Sveen said.
Advice he'll never forget after capturing the dangerous conditions firsthand on video.
The rapids at House Rock are inviting to more than just experienced boaters.
We caught up with locals who were watching the action from the shore, just like Sveen was doing on Friday evening.
Onlookers explained it's exciting to see rafters brave this section of the river.
"I like the action and the excitement of this shot at House Rock every year when the water's really high," explained nature photographer Joan Herwig.
"The most challenging is the rapid right next to us, House Rock," said rafter Jeff Wexall, "and it's the highest probability of flipping and obviously you don't want to swim this rapid."
Here are some kayaking and rafting tips from the Montana Whitewater company:
Check river conditions before heading out; make sure you have all the proper safety equipment, like a wet suit and a helmet; and, don't go past your skill level. If you're a beginner, consider taking a class or go with a guide.
We're told the rafters who fell out of the raft were all okay, but one hurt his hand and required surgery.
Editors note. This article was edited to make clear that Montana Whitewater is not associated with the people in the raft.