Houlton native Sam Johnson says he never dreamed that YouTube videos of his death defying circus act would attract producers of a reality TV show, and is still surprised that his act has advanced him to compete in week 5 of the NBC reality show “America’s Got Talent.”

Although he couldn’t reveal details, the 34-year-old single dad said that his next appearance on the show, set for 9 p.m. Tuesday, Aug. 20, is the most dangerous he’s performed on the show so far.

“I can say this,” Johnson teased in a recent phone interview. “This next one’s big. The next one is real big and it’s the most dangerous one yet. I don’t know how it’s going to translate on camera, [but] it is by far the most dangerous stunt that I will have done to date.”

On his first appearance, Johnson climbed atop an 80 foot sway pole set up outside the show’s studios, and then, completely untethered, did a handstand. For his second performance, he doused his signature top hat with gasoline and lit it on fire, before pouring gasoline over his head, and putting the hat back on. He then climbed up onto a slack line stretched across the stage, proceeded to mount a unicycle and then juggled three batons, which also were on fire.

“This next routine, it’s the first act that I bought when I was 19 years old and I performed it for three years,” said Johnson, who now lives in Vermont. “I quit performing it partly because it’s so dangerous, and partly because other opportunities were coming up in the performing world.”

Without revealing specifics, Johnson, a 1998 Houlton High School graduate, explained that he purchased the original equipment for the act from an old Swedish performer.

“This act was considered the most dangerous act on the fair circuit,” he said. “There’s only approximately six people who ever performed it. Of those six people, two of them died.”

When Johnson found out he was advancing in the eighth season of the “AGT” competition and would be performing on New York City’s infamous Radio City Music Hall stage, he knew he had to do something big. He decided to go back to his performing roots, but since the equipment was so old — it was almost 30 years old when he purchased at age 19 — Johnson had to rebuild most of what was left.

“[I] only had had a five week window to build, test and practice on this equipment,” he said.

Johnson explained that at first, he didn’t intend to audition for “AGT.” Talent scouts for the show contacted him because they were looking for a dangerous, height defying act that could be done outside. They saw Johnson online and, “initially when they called, I just fluffed it off.”

“I don’t do this anymore … I hadn’t performed for a couple of years,” Johnson said, noting that his act is very dangerous and he’s a single father to 6-year-old Phineaus. But he didn’t shut them down either.

“Three weeks before the New Orleans audition, they called [again],” Johnson said. “I thought it would be something I’d go and do once, and I’d have fun and my friends would see it. I didn’t plan to move forward in the competition, but once you get there, the bug kind of gets you.”

He’d seen a few episodes of the show in previous seasons and even has had fellow performer friends audition, but Johnson said he’s never followed a series from start to finish.

“But none of my friends that I know have gotten as far as I have,” he said. “A large part of the show is the story — the people who tend to get further have a story that others can really latch on to. Some of my friends who were on the show were in their early 20s and they were circus performers. They were phenomenal performers, but they didn’t have a great backstory.”

“It’s hard to compete with [the story of] a single dad, in my case. So many people can relate to that, and that’s going to translate into votes.”

He added that many of the competitors have really touching stories, and that others without a backstory have been more talented when it comes to raw skills, but haven’t had a powerful message to help them advance.

It’s Phineaus who drives Johnson to keep going and thinking of what he can do next to wow the audience.

“Phineaus just loves it all, but at his age he doesn’t grasp the danger aspect of it,” Johnson said. “He doesn’t like it when I leave though, and that makes it really hard.”

Johnson credits support from his parents for allowing him to pursue the AGT competition.

“Without my parents support, there’s no possible way I could pull this off,” he said, noting that his mother is 95 percent terrified and tells people to vote for her son’s competition, but is 5 percent jealous.

“My father, he doesn’t say much, but he thinks it’s great that his boy dares to do this and your boy doesn’t.”