The Sith in The Acolyte TV series is ultimately revealed to be Darth Plagueis. He appears briefly in the season finale as a hooded figure with distinct Muun features—long fingers, flat nose, and yellow Sith eyes—confirming his identity as the true Sith Master behind the scenes

. Earlier in the series, Qimir, a shady smuggler and ally of the protagonist Mae, is shown to be working under the influence of this Sith Lord, though initially Qimir was intended to be a setup for the second season's Sith reveal

. Darth Plagueis, known in Star Wars lore as the master of Darth Sidious (Emperor Palpatine), is a pivotal Sith figure obsessed with immortality and manipulating the Force at a deep level, including midichlorians

. Thus, The Acolyte explores the Sith operating in the shadows during the late High Republic era, with Darth Plagueis as the secret Sith Lord orchestrating events from behind the scenes