Jonathan Grant Thompson, the creator of popular YouTube science channel The King of Random, has died in a paragliding accident, Utah police said. (YouTube)

The host grinned and held aloft a cup of liquid boiling with thick vapor.

“This, my friends, is the real deal. This is liquid nitrogen,” said Jonathan Grant Thompson. “And this is going in my face, right now.”

Sure enough, in a nearly three-minute clip eventually viewed more than 15 million times, Thompson tossed the liquid nitrogen right into his eyes. The substance sloshed over his skin, harmlessly evaporating. And then, Thompson affably explained the Leidenfrost effect, the scientific principle behind the stunt.

Thompson’s amiable combination of edgy science, zany tutorials and easy-to-follow explanations proved a viral recipe on YouTube, where his channel, The King of Random, built an audience of more than 11 million followers and racked up more than 2.5 billion views while occasionally landing Thompson in trouble with authorities in the Utah neighborhood where he filmed shows in his backyard.

On Monday, Thompson’s latest adventure ended in tragedy. Police in southern Utah confirmed that the 38-year-old died in a paragliding crash in a remote region of craggy peaks and steep valleys, the Salt Lake Tribune reported. Police recovered video footage at the scene.

“Grant had great love and appreciation for his fans,” said a memorial posted on The King of Random channel. “Please do a random act of love or kindness today in honor of The King of Random. Grant’s legacy will live on in the channel and the global community he created.”

Thompson said the channel grew out of his interest in learning the inner workings behind the basic necessities of modern life — a hobby sparked by his fears during the 2008 financial crisis.

“There was a lot of real estate foreclosures and talks of depression, and I wanted to be the guy who was prepared for any emergencies,” Thompson said in a video posted last year. “So I was taking apart microwaves and playing with electronics and just trying to figure out how society worked and how to reverse engineer that at home.”

He started the channel in 2010 after showing his brother and a friend some of the tinkering he’d filmed. The friend told him, “Dude, you’re like the king of random,” inspiring his online moniker.

On a channel “dedicated to exploring life through all kinds of life hacks, experiments, and random weekend projects,” Thompson came across as a combination of Bear Grylls and MacGyver as he whipped up backyard science projects, shared zombie apocalypse-worthy survival tips and narrated oddball DIY home projects.

His videos, which he described in one shot as “mad science,” whipsawed from potentially useful tidbits — from getting better cellphone reception to starting fires with a plastic bottle of water — to bizarre how-to’s like melting down bullet shells into brass-knuckle paperweights. A video about cooking up Lego-shaped gummy candy became his most viral upload, with more than 34 million views and counting.

He also relished in science projects with a boom, from creating homemade gunpowder to turning water bottles into exploding targets for slingshot practice. That particular genre of video eventually landed him in court.

In January 2018, police in South Jordan, a suburb of Salt Lake City, started investigating after someone sent in a link to a video of Thompson creating a “bomb” by stuffing dry ice into a Coke bottle, the Tribune reported. A month later, authorities showed up at his house when he set off an explosion loud enough to rattle a nearby firehouse. This time, police said, Thompson told them he’d ignited a pile of mysterious powder, possibly from disassembled fireworks.

He was charged with two counts of second-degree felony possession of an explosive device. He disputed that he’d done anything unsafe, lamenting to the Tribune that the arrest “makes it seem like I am an irresponsible YouTuber who is blowing stuff up.”

Four months later, he reached a deal with prosecutors: They’d eventually erase the charges if he made two videos warning others to be careful with explosive experiments. He also promised not to disturb his neighbors with any other loud bangs while filming his show.

Thompson got into paragliding about five months ago, his brother, Mark, told TMZ. On Monday, the YouTube star took off in a glider near Sand Hollow State Park in Hurricane, Utah. Police began searching when he didn’t return as planned and were soon able to pinpoint his last known GPS location, the Tribune reported. A medical helicopter located his body and crashed paraglider. Police don’t suspect any foul play, according to the Tribune.

Before his death, Thompson had recently shifted to a role behind the camera, bringing in new hosts so he could spend more time with his wife and four children. He told viewers that he’d previously been working “16 hours a day, six or seven days a week,” and was nearing a burnout.

“At first, it was really fun to get views on the videos, but when things started to explode, that load got heavier and heavier and heavier and I was the only one carrying it,” he said. “I couldn’t see a way to keep balancing this on my own.”

The channel kept growing without Thompson on camera, though, and he told viewers last year that working with a larger staff and a more ambitious filming schedule had changed his life.

“I feel better than I ever have and I feel very optimistic about the future,” he said. “I love you guys.”