On Etheria, an oppressed planet ruled by the tyrant Hordak, the evil leader of a band of evil creatures called The Evil Horde. Force Captain Adora, a beautiful human woman who loyally serves Hordak meets a mighty warrior called He-Man who has travelled to Etheria from his own planet Eternia to give to Adora a magic sword called The Sword of Protection anrd is stunned when He-Man's mentor The Sorceress of Greyskull reveals to Adora that she is He-Man's long-lost twin sister and exposes to her terrible truth that many years ago, Hordak stole her from the rightful rulers of Eternia King Randor and Queen Marlena and brought her to Etheria to serve him. Learning the truth and that Hordak is not a good and wise ruler, but a cruel tyrant who oppresses the people of Etheria, Adora betrays Hordak and sides with The Great Rebellion, a band of rebels that is fighting to free Etheria from Hordak. Raising the sword, Adora magically transforms into the mighty warrior princess She-Ra. Together with the Great Rebellion, She-Ra sets out to defeat Hordak and the Evil Horde and bring freedom to Etheria and it's people.