Invincible season 3 post-credits scene is a tease for a hellish comic storyline adaptation that Robert Kirkman "never got around to doing"

Invincible creator Robert Kirkman has teased more of what to expect after season 3's hellbound post-credits scene – and it's bringing in material that was ultimately left out of the comics.

In the Invincible season 3 ending, the Hellboy parody Damien Darkblood (Clancy Brown) is plotting away in Hell.

Last we saw him – way back in the first season – he was banished by Cecil (Walton Goggins) after cracking the Guardians of the Globe mystery. Now, he has summoned a demonic lord (played by Bruce Campbell) and plots to conjure a "surface dweller of great power" and use him to bring his master back to his rightful place on the 'infernal throne' of Hell.

As comic readers may know, however, this is a major deviation from Robert Kirkman, Cory Walker and Ryan Ottley's source material.

Speaking to Variety, Kirkman explains that he "always wanted to figure out" how to get Darkblood back into the show. His plan? To use a scrapped storyline that never made its way into the pages and panels of the Image Comics series.

"There’s a storyline from the comic that I never got around to doing. Every superhero story has some chapter where they go to hell and they fight the devil. It happens in DC and Marvel comics. It’s a big deal," Kirkman explains.

"I never got around to doing anything like that in Invincible. I kept getting sidetracked and there was never a good time. So it’s entirely possible that we may be doing something like that in the show, and that scene at the end of that episode is setting that up."

While Kirkman was reluctant to offer more, he did inadvertently let slip a detail about Bruce Campbell's hellbound character – and he could be Old Scratch himself.

"Could be the devil. Could be. We’ll just have to see," Kirkman teased. "Maybe I shouldn’t have spoiled that."

Expect to find out more in Invincible season 4, which has been officially greenlit and is slated for 2026. If you need something to fill the Viltrumite-shaped hole in your life, check out these picks for the best shows on Prime Video.