Near Castle Grayskull Man-At-Arms looks on as Prince Adam and Teela climb up a large cliff face with Cringer. Man-At-Arms sees that the Evil Warriors, atop their Griffins, approaching Castle Grayskull. Man-At-Arms and Teela quickly head off to confront the Evil Warriors on their Battle Hawks, as Adam and Cringer transform into He-Man and Battle Cat. The Masters battle the Evil Warriors near Castle Grayskull, and having been defeated the villains depart on their Griffins. Man-At-Arms reveals to the Masters that The Council of Elders transformed themselves into a magical crystal orb that now lies hidden deep within Castle Grayskull. Ram Man states that the Masters of the Universe should all take an oath of loyalty. Buzz-Off states that he has already proven his loyalty and does not need to recite an oath. At Snake Mountain Evil-Lyn suggests turning the Masters against one another by turning Ram Man into a traitor.
Later Ram Man is in a small boat, when a large wave causes Ram Man and his boat to crash. When Ram Man awakens Sersi the Siren stands over him. Sersi tells Ram Man that when he hears her song he shall do as she says. At the Royal Palace Man-At-Arms demonstrates his new invention the Immobilizer to the other Masters, not knowing that a Doomseeker spies on them. Ram Man under the influence of Sersi enters Man-At-Arms' laboratory, knocks an unaware Buzz-Off out and takes the Immobilizer. Ram Man awakens with no memory of what has happened. Man-At-Arms states that whoever took the Immobilizer knew how to deactivate the alarms. Ram Man accuses Buzz-Off of treachery.
As the two begin to fight Prince Adam quickly leaves. He-Man stops Ram Man, and Buzz-Off leaves in disgust. Ram Man walks out, under the command of Sersi. Prince Adam and Teela follow Ram Man as he makes his way towards the lagoon. Ram Man hands over the Immobilizer to Sersi, who reveals herself to be Evil-Lyn. Later at Man-At-Arms' laboratory the Masters confront Ram Man. King Randor announces that a hearing is in order, as a Doomseeker spies on them. Imprisoned, Ram Man hears the voice of Sersi once more, and rams through the jail cell wall. The Masters board the Bashin' Beetle and chase Ram Man. They eventually stop when confronted by the Evil Warriors and Evil-Lyn, still in the guise of Sersi.
Skeletor produces the Immobilizer and freezes the Masters. Skeletor is shocked when all the heroes begin to move. Man-At-Arms reveals that the Immobilizer requires a special activation code. Buzz-Off takes the Immobilizer, and hands it to Man-At-Arms, who freezes Skeletor and his Evil Warriors, except Evil-Lyn. Man-At-Arms reveals to the frozen Skeletor that while Ram Man was at the Royal Palace he discovered the spell he was under, and gave him a microchip to block the spell. The Masters reveal that they are all wearing a microchip. Evil-Lyn using the now activated Immobilizer freezes the Masters, as Adam and Cringer transform into He-Man and Battle Cat.
Evil-Lyn threatens Skeletor stating that she should use the Immobilizer to obtain the power of Castle Grayskull and conquer all, even Skeletor himself. Evil-Lyn transforms back into the form of Sersi and begins to control He-Man's mind. Sersi turns the ground around He-Man into a lava pool. Sersi commands He-Man to walk into the lava. Fortunately Ram Man rams a tree, which strikes Sersi, breaking her control over He-Man. The Immobilizer falls into the lava and its control over the Masters and the Evil Warriors is broken.
Back at the Royal Palace Ram Man apologizes to all the gathered Masters.