In the Season 1 finale of The Lord of the Rings: The Rings of Power, it was definitively revealed that Halbrand was the Dark Lord Sauron. This revelation was shocking to some fans and not surprising to others given how The Rings of Power hinted at Halbrand's identity throughout the season. Given the fact that the show pulled a red herring with the Stranger, it's not surprising that fans are suspicious of Sauron's true identity.