When Max and Isabel's mother disappears in front of their eyes, the two discover all of the other humans are gone as well. Max then makes a call to Michael, who is helping Courtney put on her new husk, to tell him to meet at the Crashdown. At the same time, Liz and Maria have returned from running an out of town errand for Liz's dad to discover the entire population of Roswell missing. When Liz finds a piece of alien skin on the ground, she and Maria run to the Crashdown where they tell the others what they found. As Tess begins to interrogate Courtney about what happened, Isabel notices Nicholas coming toward them. In order to hide, they all gather into the restroom where Tess creates a mind warp. Satisfied the Crashdown is empty, Nicholas leaves. Feeling scared, Liz goes upstairs and is followed by Max. As the two of them share an awkward moment, they hear a scream from downstairs and soon discover a dying Courtney on the ground. Courtney explains her husk wasn't ready when she put it on, and says it's literally feeding off of her due to a lack of nourishment.
After putting Courtney into a bath of vitamins, Tess and Isabel demand to know what is going on. Courtney explains that Nicholas must have the technology to impose multiple subset dimensions, as they exist on their home planet. She explains it would be like living in Pacific, Eastern, Central and Mountain Time all at once, something in which human bodies can't function. Courtney then explains the humans are probably in another dimension, and says Liz and Maria will soon too disappear. With this new information, Maria and Liz proceed downstairs where a Skin confronts them. As the Skin tries to grab them, Sheriff Valenti shoots it in the back. Unaffected by the bullet, the Skin pushes past the Sheriff and Kyle and runs out the door. Now feeling better, Courtney tells them the only way to kill a Skin is to hit it in the back at the place of the seal of the husk. Max then tells everyone to go to the UFO Center where they can best monitor the movement of the Skins. As Max and Isabel stay behind to make sure everyone has safely gotten into the Center, Isabel tells Max she is going after Nicholas. Max objects, but Isabel goes anyway and is caught. When Isabel attempts to trick Nicholas, Ida throws her leaving her unconscious.
Back inside the UFO Center, Courtney tells Michael the only thing that can save her is the Granilith. Courtney then disappears, as Kyle and Liz realize the energy field that caused the human disappearance may be coming from a billboard Kyle and his father passed on their way back in town from a fishing trip. After Kyle watches his father disappear, he decides to go back to the billboard to destroy the device, which is probably some type of generator. Max objects, but Kyle, Liz and Maria go saying they have to try. Meanwhile, Nicholas has captured Courtney and is attempting to retrieve her memories. Wanting to protect the location of the Granilith, which Michael exposed to her, Courtney destroys herself but not before Nicholas learns that Max and the others have gone to the high school. Nicholas leaves Isabel at the school, and successfully captures Max, Michael and Tess. Nicholas reveals to Michael that he was the one who spilled the secret of the Granilith to one of their exiled members. He then tells Michael that Courtney killed herself to save their secret. As the Skins watch, Nicholas attempts to retrieve the location of the Granilith from Max inflicting him with a great pain. Unable to stand Max being harmed, Tess attempts to create a mind warp but soon loses control of her powers creating a wall of fire that destroys the Skins. At the same time, and after Liz and Kyle have disappeared, Maria destroys the alien generator and we see the entire town reappear as if nothing had ever happened.