Casting for the prequel "The Witcher: Blood Origin" has already begun, and Netflix is eyeing Jason Momoa for the lead role.

A Sept. 2 casting call report from Production Weekly specifically mentioned the "Game of Thrones" actor as one of the cast members for the upcoming show. The source placed his name at the bottom right after the show's synopsis.

This would possibly explain the viral fan art of Henry Cavill's Geralt of Rivia and Momoa. The "Frontier" star even shared it on his Instagram Story and tagged the Superman actor.

Rumours on the "Aquaman" star's involvement in "The Witcher: Blood Origin" originally trended online two weeks ago. We Got This Covered first reported on the casting as told to them by a reliable source, the same one who said that a prequel was in the works before Netflix confirmed it.

"The Witcher: Blood Origin" will be a six-part live-action limited series that is set in an elven world 1,200 years before the events of "The Witcher." It will trace the history of the very first monster hunter, and "the events that lead to the pivotal 'conjunction of the spheres,' when the world of monsters, men, and elves merged to become one."

Declan de Barra will serve as showrunner. "The Witcher" creator Lauren Hissrich will serve as producer along with Jason Brown, Jarek Sawko, Sean Daniel, Tomek Baginski, and Andrzej Sapkowski. Filming for the series will mainly take place in parts of the United Kingdom.

Meanwhile, filming for "The Witcher" Season 2 is ongoing and is set to wrap up in February 2021. It is likely that production for "Blood Origin" will follow thereafter.

If the casting call is right and if his deal with Netflix pushes through. then Momoa will likely portray the very first Witcher in "Blood Origin." The actor has yet to comment on the rumours but him showing interest in the fan art may serve as a clue. It would not be a surprise to see him in yet another fantasy TV series after "Game of Thrones" and "Stargate Atlantis." He definitely also knows his way around shows that have historical themes.

Jason Momoa
Jason Momoa Gustavo Caballero / Getty