In Unfinished Tales, J.R.R. Tolkien suggests that the two Blue Wizards ... about the fates of Alatar and Pallando. The Rings of Power showrunners have suggested the Dark Wizard's identity, and ...

It also makes way more sense their Dark Wizard is really one of the Blue Wizards we know so little about. But not matter what his true identitywhether he’s Saruman, Alatar, Pallando, Radagast ...

or a Wizard sent to Middle-earth. There were five Istari sent to Middle-earth, according to The Lord of the Rings, Gandalf, Saruman, Radagast, and the Blue Wizards, Alatar and Pallando.

and two Blue Wizards called Alatar and Pallando (alternately named Morinehtar and Rómestámo). So, if the Stranger is Gandalf, then that means the Dark Wizard is either Saruman, Radagast ...