'The Boys' showrunner says he knew Jensen Ackles could pull off playing Soldier Boy after working with him for years on 'Supernatural'

• Warning: There are major spoilers ahead for season three of Prime Video's "The Boys."
• Showrunner Eric Kripke spoke to Insider about Jensen Ackles' arrival this season as Soldier Boy.

"The Boys" showrunner Eric Kripke said he was eager to show fans Jensen Ackles' versatility as Soldier Boy in season three, after working together for years in "Supernatural."

"I was just excited to show the world a different side of Jensen, because I knew he could do it," Kripke told Insider at a virtual press junket for "The Boys" in early June.

Kripke and Ackles met through The CW's "Supernatural," which lasted for 15 seasons between 2005 and 2020. Kripke created the fantasy drama series and Ackles starred alongside Jared Padalecki as brothers Dean and Sam Winchester, respectively.

Although Kripke stepped down as the showrunner of "Supernatural" after season five, he and Ackles continued to stay in touch over the years.

The actor was already a fan of "The Boys," which premiered on Prime Video in July 2019. With the conclusion of "Supernatural," he voiced interest in being part of the show.

After auditioning, Ackles landed the role of Soldier Boy, a supe that he described as a "jackass" and "curmudgeon, bigoted asshole."

"After spending 15 years as one particular character, I was looking forward to showing just a totally different character entirely, which I knew he could pull off," Kripke said.

"I mean, when you know an actor as well as I know Jensen and have seen literally hundreds of hours of film on him, I can write with a lot of confidence because I know exactly what he can do," he added.

In "The Boys," Soldier Boy was allegedly killed by an unknown weapon decades prior.

This sparks the interest of the anti-supe vigilante group known as the Boys, who seek out the weapon in the hopes that it's powerful enough to take down The Seven's physically strong but emotionally unstable leader, Homelander (Antony Starr).

Episode four showed the Boys traveling to Russia in search of the aforementioned weapon — only to come face-to-face with Soldier Boy.

But before that, the episode opened with a cheesy flashback of Soldier Boy guest-starring on the variety show "Solid Gold" and performing Blondie's "Rapture."

Episode five revealed that Soldier Boy was repeatedly experimented on by the Russians in a lab and exposed to high levels of radiation. After years of captivity, Soldier Boy heads to New York, where he gets triggered and accidentally emits a blast of energy that wipes out a building.

When the Boys finally caught up to Soldier Boy, they struck a deal in which he agreed to help them kill Homelander.

"One of the things I love about Jensen is how versatile he is," Kripke said, adding that the actor is adept at tackling comedy, drama, horror, and action. "He tends to always be able to pull it off. So I knew that would be perfect for all the different colors of Soldier Boy."

The first five episodes of season three of "The Boys" are now streaming on Prime Video, with the remaining three episodes dropping weekly through July 8.