The first television offshoot of the Marvel Cinematic Universe, Agents of S.H.I.E.L.D., found its footing late in season 1 in the aftermath of the Captain America: The Winter Soldier tie-in episode that saw S.H.I.E.L.D. disavowed when it was revealed to be overrun by Hydra agents. In the show's second and third season, Phil Coulson's (Clark Gregg) team largely focused on discovering and learning more about Inhumans. One such storyline focused on Skye (Chloe Bennet), who learned that father was Cal Zabo a.k.a. Mister Hyde (Kyle MacLachlan), she was an Inhuman, and her real name was Daisy Johnson - a.k.a. Quake from the Marvel comics.
However, the upcoming fourth season of Agent of S.H.I.E.L.D. will shift the focus away from Inhumans and to less scientifically explainable aspects of the MCU - namely, the series will introduce Robbie Reyes a.k.a. Ghost Rider (Gabriel Luna). In the comics, Robbie's origin story to becoming Ghost Rider was intertwined with Mister Hyde, who ordered mercenaries to kill Robbie and torch the scene. Instead, Robbie made a deal to become Ghost Rider and was revived, eventually going on to defeat Zabo.
Since Mister Hyde is a part of Robbie's origin story, TV Line asked Agents of S.H.I.E.L.D. co-showrunner Jed Whedon whether MacLachlan will reprise his role on the show (he was last seen at the end of season 2 with his memories wiped and no knowledge of S.H.I.E.L.D. or his daughter). Whedon said that although he'd like to see MacLachlan return, Robbie's origin story will be different than in the comics:
“We can’t say much about what we’re going to do with [Robbie Reyes’] origin, but we are doing our own spin on it. We don’t want people who have read the comics to know exactly what’s coming.”
So, it may be safe to say that since Cal Zabo is wrapped up with Robbie's transformation into Ghost Rider in the books, and the Agents of S.H.I.E.L.D. origin of the character will be different, we likely won't be seeing MacLachlan return to the series to tell this particular story, even in flashback form. Still, we do know that when Robbie is introduced, it will be unclear whether he's friend or foe to S.H.I.E.L.D. - as seen in set videos of Daisy taking on Ghost Rider's car.
“Not sure they like each other. Not very happy interactions. They have similar backgrounds. They’re both probably misunderstood, but none of that. She’s really hurting. She’s in a lot of pain. The only thing she wants is to have nothing to lose.”
Given Bennet's comments, it seems Daisy will meet Robbie while she's still dealing with the fallout from the season 3 finale, specifically the loss of Lincoln (Luke Mitchell). Still, Ghost Rider isn't the only new addition to season 4 since S.H.I.E.L.D. will have a new director and the series will be exploring Life-Model Decoys. How everything ties together remains to be seen when Agents of S.H.I.E.L.D. season 4 premieres next month.
Agents of S.H.I.E.L.D. season 4 premieres Tuesday, September 20 @10pm on ABC.