The fourth season of ABC's Agents of S.H.I.E.L.D brought another Marvel character in the form of Ghost Rider, though using a lesser known Robbie Reyes than the iconic Johnny Blaze. As the character was taken positively by fans, the identity of the previous Rider, while hinted, is still shrouded in mystery.

In an interview with IGN at the set of the show, executive producers Jed Whedon and Jeff Bell did not just leave the mystery as is, but they also implied that the character won't be making an appearance anytime soon. According to Bell, their take on the Ghost Rider tradition is that the Spirit of Vengeance is passed from one person to another. This would mean that in their view, there won't be more than one Ghost Rider at a time. As for the one who passed the spirit to Robbie, they did not reveal its identity, and it seems that it would be left as it is.

While building up on the Ghost Rider and his powers, the episode 'The Good Samaritan' showed how Robbie Reyes received the Spirit of Vengeance from another person. As Screen Rant reports, many assumed that it was Johnny Blaze, based on the leather jacket and the motorcycle. Other hints, like the poster for the Quentin Carnival seen on the episode 'Lockup', as well as the scar on the Rider's left eye further cements the identity of the Ghost Rider.

Agents of S.H.I.E.L.D, which resumed airing on January 10, has currently shifted its storyline from the Ghost Rider arc to LMD or Life Model Decoys, an idea they have been toying with since the inception of the show. As it has always been a part of the history of S.H.I.E.L.D, the delay of its introduction to the show was due to the fact that they wanted to use Avengers: Age of Ultron as a catapult for the idea.

Agents of S.H.I.E.L.D can be seen on ABC every Tuesday.