Instead of going to school, Rob and Chris drive out of town and take the ferry to reach the coast. Chris gets excited when she learns that it will be Rob’s first time going there, especially since she associates many happy childhood memories with the area. They descend to the beach and change into beachwear. Chris leads Rob to a large rock formation that she likes visiting. It is a stone arch that extends out of the water.

The couple runs to the rock so that they can let the waters cool their bodies afterward. Chris takes off her clothes and urges Rob to do the same. Though the cold makes Rob reluctant at first, he eventually becomes comfortable and tells Chris that he loves her. Chris asks him to be sure of what he is saying. Rob assures her that he is, stressing that he would never lie to her. Chris reciprocates his love and promises that she will love him forever.

After swimming, Rob and Chris eat and lie down on the beach. Chris wants the day to last forever but resigns herself to leaving the beach at sunset. They ascend to a nearby ridge and set their things down. They share a bottle of wine and kiss, which Chris experiences as more powerful now that they have acknowledged their love for each other. As night falls, Chris invites Rob to have sex. Chris extends the experience for as long as she can and then watches the night sky as Rob falls asleep. Rob’s second mouth starts talking, saying that it is impossible for things to work out. Chris panics and tries to wake Rob up.

Back at the camp, Chris smokes and reminisces about her day with Rob at the beach. The day after they arrived, dark clouds loomed over the water, making the beach feel different. They drove back home later that day, and Chris promised to call Rob soon. Once she got home, Chris was confronted by her mother, who had been informed that Chris was frequently skipping school. Chris’s mother demanded to know the truth about where she had been, suspecting that a boy was involved. When Chris refused to tell the truth, her mother grounded her indefinitely.

Chris informed Rob that her parents had scheduled an appointment with a gynecologist for later that week. Afraid that this would expose her illness to her family, Chris started planning to run away from home with Rob’s help. As the week went by, Chris struggled to act normally while taking stock of the life she was leaving behind. On the eve of the gynecologist appointment, Chris’s mother noticed that Chris looked unwell, but Chris shrugged it off as the strain of studying for her geometry finals. Chris called Rob to pick her up and then left a note to tell her parents that she was running away to California. Before she left, she told her little brother that she was stepping out. She hugged him and told him to be good, which confused him.

Rob took Chris to the park and led her to the camp. He introduced her to Dave, who remembered Chris from school. Chris tried to convince herself that she was going camping like she used to as a child. Dave and Rob helped her to set up her campsite. Dave invited Chris to join their community campfire, also called The Pit. After Dave left, Chris indicated that she was unlikely to join them because she just wanted to be with Rob.

In the present, Chris anticipates that Rob will arrive soon. She spends most of her days waiting for Rob to visit her. When she steps out of her tent, Chris hears someone nearby. She goes to investigate and finds a sculpture of doll parts bound to a tree by sticks and string. This makes her jumpy when Rob does arrive. She shows him the sculpture, which Rob recognizes as similar to other sculptures he has seen around the woods. He tells her not to worry. Chris is unsure whether she can live this way and asks Rob for reassurance.

Toward the end of summer, Keith walks home with a popsicle and encounters the woman from Burt’s house sitting on her porch. The woman recognizes Keith and compliments his new haircut. Keith explains that he got one for his part-time job. The woman assumes Keith is there for drugs and tells him that Burt and his friends are away. She asks for a bite of Keith’s popsicle but accidentally breaks it, causing the house dog, Faust, to eat it. Keith learns that Faust broke his leg in a car accident caused by Burt and his friends’ neglect. The woman saved Faust’s life by taking him to the vet. She invites Keith to stay with her, offering him marijuana and apologizing for her moody behavior.

Keith follows the woman inside. The woman shares that she used to clean up after Burt and his friends as part of her residency deal, but now she is sick of them and wants to move elsewhere. The woman explains the meaning of the graffiti written on her door: Burt and his friends call her “Lizard Queen” to make fun of her tail. “Lizard” is also derived from her real name, Eliza. Keith is surprised to find that Eliza’s room has been emptied of its artwork. Eliza offloaded them in anticipation of her move, though she had also become sick of them.

Keith quietly rolls a marijuana joint for himself and Eliza. In the middle of smoking the joint, Eliza suddenly laughs. She explains that she is laughing at the absurdity of their feigned seriousness. She relitigates their last encounter and reminds Keith that he doesn’t have to stay if he doesn’t want to. Keith assures her that he wants to stay. They kiss, which makes Keith extremely aroused. Keith realizes how high he is when Eliza sits atop him. Though he knows he has the power to tell her to stop, he lets go of his inhibition and allows her to indulge his arousal. When she licks another joint that she is rolling, Keith ejaculates in his pants. He excuses himself to clean himself up.

In the bathroom, Keith looks at pornographic magazines that have been stacked on the toilet. He reflects on how poorly the environment at the house fits Eliza. Just then, he hears Burt and his friends arrive. One of Burt’s friends turns aggressive at the sight of Keith, refusing to hear his explanation of how they know each other. Burt gets his friend to back off, allowing Keith to return to Eliza, who is fully nude and bathed in red light.

Eliza gets Keith to lock the door. They share the joint that she is smoking. The sight and smell of Eliza’s body motivate Keith to take off his clothes. They have sex, initially with Eliza on top of Keith. She later invites him to go behind her, using her tail to caress him. Eliza tells Keith to grab her tail as their activity intensifies. Part of the tail snaps off, causing Keith to panic. Eliza reassures him that it will grow back. Afterward, Eliza continues to reassure Keith that it didn’t hurt to lose part of her tail. She tells him how much she enjoys being with someone again, thanks to him, and falls asleep. Keith is still holding the fragment of Eliza’s tail when he hears the sound of Burt, his friends, and Faust outside the room.

Rob tells Chris that he needs to go home to avoid his mother’s suspicion, though he will return to bring her dinner. They reiterate their love for each other before they part ways.

As Rob navigates the woods, he bumps into the same person who was watching the camp residents and Keith’s friend group from afar. The man uses his pipe to beat Rob down and bash his face in. He explains that he was instructed to kill Rob. As Rob dies, his second mouth apologizes to Chris that things didn’t work out.

Chris calls out for Rob, believing that he is nearby.