The Skins make all the humans in Roswell, New Mexico disappear turning it into a ghost town. Their assault ends with the death of one of the aliens: Courtney the helpful Skin. Fortunately Tess uses her mindblowing powers and destroys all the other Skins or so it seems until Max and Tess spy a boy resembling Nicholas on a scooter at the end of the episode.
Max, Isabel and Michael have been hiding a secret for their entire lives - that they come from a different planet. When Max is exposed while saving Liz's life, a girl who attends their high school, it eventually leads to a few others learning their secret. The three aliens and their new friends try to go about their normal lives while trying to discover more about where they come from and how to get home - all while keeping their identities secret from the rest of the world.