As Liz and Maria deliver drinks to Max and Michael at the Crashdown, Max’s notebook gets knocked onto the floor, revealing a pencil sketch of the cave painting that River Dog showed Max several weeks earlier. Michael grabs it, incensed that Max has been hiding this from him. Equally upset over Max’s secretiveness, Isabel, like Michael, recognizes the drawing as some sort of alien language, but cannot remember how to read it.

That evening at the café, Alex tells Maria that he has been researching what Liz told him in jail by renting the Alien trilogy, but he still thinks that she and Liz may be crazy. Out in the desert, Michael arrives at the Indian reservation, looking for River Dog. Eddie, the young Native American who served as an intermediary for Liz and Max, informs him that River Dog is leading a ritual cleansing in the sweat tent. Not to be deterred, Michael takes off his shirt and joins about a dozen Native American men in the tent.

Isabel soon joins Alex at the Crashdown and he begins to interrogate her about her alien origins, asking how they could take on human form, how they have avoided detection and what they are doing on earth. She admits that she wonders about those same things, but she says that they are just normal humans, except for their ability to manipulate molecular structure. After making sure no one is watching, Isabel proceeds to turn the ketchup into mustard and vice versa. Stunned, Alex chokes on his soda.

At the sacred cleansing, River Dog picks up a bowl and takes a sip of what is inside, then passes it on to the next man. When Michael’s turn arrives, he looks River Dog in the eye, takes two sips and passes the bowl on to Eddie. At this point, men begin to succumb to the heat and leave the tent. Michael tries hard to endure it and prove himself worthy of River Dog’s attention, but finally the smoke gets so intense that Michael runs out of the tent gasping for air. Angry at himself and the situation, Michael reenters the tent to find River Dog gone. He suddenly feels a chill.

Back in town at a Chinese restaurant, Liz and Max become romantic over fortune cookies. Just as Liz lets him know that her parents are gone for the weekend, Maria bursts in and tells them that Michael has been taken ill at the Crashdown. They all arrive at the café to find Michael shivering and sweating. Hating this kind of attention, Michael claims to be better and asks to go home.

The next day at the UFO Center, Alex tries to help Isabel by showing her an ancient stone tablet that looks figuratively similar to the cave painting, but she dismisses him, saying that they have already checked it out. They hear a commotion nearby and find that Michael has collapsed. Max and Isabel carry Michael to the back of the Crashdown, where they ask Liz if they can keep him upstairs until he gets better. Nervous and hesitating, Liz agrees. Max and Isabel are very worried, as none of them has ever been sick before. To make matters worse, since Max does not know what is wrong, he cannot use his powers to heal Michael.

Regaining consciousness briefly, Michael whispers to Max the name of River Dog. Now that Max has a clue, he and Liz go out to the reservation where Eddie tells them that Michael did not pass River Dog’s test. Furthermore, River Dog is angry with them for breaching confidentiality and telling Michael about him. Max wanders the reservation, telling Liz how he first saw Michael after they came out of their pods. When he and Isabel were taken away, Michael ran into the desert and they did not see him again for three years. Liz and Max come to the sweat tent where they find River Dog, who has been told by Eddie the gravity of Michael’s illness. He tells the young couple to bring Michael to him.

Max, Liz, Isabel, Maria and Alex return to the reservation with Michael, who now has the wisps of a cocoon growing all around his body. They take him to the cave with the painting, where River Dog arranges stones in a precise order around Michael’s body. River Dog tells them that the alien who lived in the cave when he was a boy also became ill after being in the sweat tent. The "visitor" told River Dog how to heal him and he will try to repeat the procedure, but he needs the energy of everyone there. They all take places around Michael, like spokes on a wheel, and pick up the stones that River Dog got from the alien.

The alien stones contain an energy that will restore the balance to Michael body that was disrupted by the heat from the sweat tent. If they all concentrate and stay true to their friend, he will recover. After hesitating, Liz follows River Dog’s instructions and Michael sits up abruptly, back to his old self. He has learned from a hallucination while feverish that the cave painting is a constellation, a map to their home.