On Beast Island, a group of conceals, the race of beings of which Loo-Kee is a member, is running for their lives away from a pack of robotic dogs, which Catra dubs the Terror-Terriers. Catra is rounding up the conceals and capturing them, so that she may imprison them for their illegal acts of bringing fruit and vegetables into the Fright Zone and feeding the slaves. She captures Poppy, who is Loo-Kee's father, leaving only a young girl conceal named Laa-See to race to the Whispering Woods, in the hope of getting help from Loo-Kee or the Great Rebellion. Laa-See dives into the sea and goes to seek help.
Meanwhile, back in the Whispering Woods, Loo-Kee has revealed himself to Adora and is eating by the campfire with her. Suddenly, they hear Laa-See's cries for help, and discover that she has surfaced in a well in the Whispering Woods. She tells Loo-Kee that his father has been captured, and that the conceals need help. Adora runs to find cover so that she can become She-Ra. As She-Ra, Loo-Kee, and Laa-See race back to Beast Island, Catra's ship intercepts them and she attempts to use a battalion of Batmeks to shoot She-Ra out of the sky. She-Ra destroys the Batmeks and engages Catra in a battle amongst the clouds. She-Ra strikes the engines of Catra's plane, causing it to crash into the sea. She-Ra, Loo-Kee, and Laa-See arrive at Beast Island, as Catra is picked up by a Horde ship. Catra orders the full defenses of Beast Island to be activated. Laa-See suggests that they enter Beast Island using the tunnels that the conceals had been using to feed the prisoners. However, Catra has planned for this particular contingency and has set a trap.
They all fall down a hole, She-Ra and Laa-See splashing into the slime that awaits them at the bottom. She-Ra and Laa-See are trapped in the Horde's newest security device, the Slime Pit. Loo-Kee dangles above, having used his tail to avoid falling into the pit. At that moment, Mr. Slime Pig emerges from the slime and reveals that he has a liquid, which will permit them to escape the sticky slime, but he refuses to share it. Loo-Kee leaps down on Mr. Slime Pig's head and steals the liquid, but She-Ra orders him to give it back. The rebels do not take things that do not belong to them. Loo-Kee gives it back and apologizes to Mr. Slime Pig for taking it, and this act of kindness prompts Mr. Slime Pig to help them escape by using the liquid. They escape from the Slime Pit and arrive at the surface, where She-Ra tosses the Horde freeze cannon at the force-field, disrupting the field and allowing the conceals to escape. She also tosses Catra into the Slime Pit to wallow along with Mr. Slime Pig, while Loo-Kee and the other conceals regain their freedom. Loo-Kee is especially grateful to She-Ra for her help in freeing his father and his people.
Synopsis by Michael Cravens