Mark Grayson (Steven Yeun) becoming the hero known as Invincible. Kirkman's giant universe is now being adapted as a TV show and comic readers can already start to see how Invincible is planting seeds for stories to come.
Amazon released the first three episodes of Invincible at once, giving viewers a chance to see a great deal of the eight-episode first season right away. The story still revolves around Mark, his father Omni-Man, and the superhero universe, but it has also wasted no time setting up the Mauler Twins. The geniuses have an incredible understanding of the cloning process, although both of them believe they are the original Mauler and not the twin. They're featured in Invincible's opening action set-piece and wind up in prison due to their attack on the White House.
The Mauler Twins don't spend too long in confinement though. The end of Invincible episode 3 saw the Mauler Twins escape from the supervillain prison that held them. While one of the Maulers found a way to initiate the breakout, they got some extra and unexpected help. Invincible reveals that Robot, the leader of the Guardians of the Globe at the time, was the secret benefactor who helped them escape. Robot's place among the heroes makes his decision to help two notable villains escape especially curious. However, the Invincible comics likely hold the key to why Robot helped the Mauler Twins.
Part of Robot's story in clone body of Rex Splode.
It appears that Invincible is already setting up a connection between Robot and the Mauler Twins to set the stage for this story to play out. What remains to be seen is whether or not the show will get to this part of Robot's story during season 1. The reveal happens throughout volume 7, but the transformation is completed in issue #34. It would be somewhat surprising if the animated series progressed that far during season one but we can't rule it out. If it doesn't, the Mauler Twins will still play a big role in the rest of Invincible season 1 based on their comic roles.