The narrator, a Canadian woman, is driving north with her boyfriend Joe and their married friends David and Anna. Her father has gone missing on a remote island, and the narrator is going to look for him. Meanwhile, David and Joe are working on a documentary called Random Samples, filming objects they encounter on the trip. When the group arrive at the village near the island, the narrator finds Paul, who informed her of her father’s disappearance. Paul’s wife Madame gives the narrator her condolences over her mother’s death. Once Paul explains that he and the police have looked around the island where the narrator’s father vanished, she announces that she will go look herself. Paul asks whether her husband is with her. She says yes, thinking it’s lucky that she’s still wearing her ring and that her parents never told Paul about her divorce. The narrator returns to her friends and suggests they go stay at her father’s island cabin. An American named Evans boats them to the island, agreeing to pick them up in two days.
In the cabin, the narrator notices papers on a shelf. The next morning, the group searches for the narrator’s father. When they return to the cabin, the narrator rifles through the papers she saw. They contain bizarre, numbered drawings of half-animal, half-human figures. The narrator, wondering whether her father went insane in the isolated cabin, returns the papers to the shelf. That night, David wants to go fishing. He catches nothing until the narrator puts a frog on his hook for bait. The next morning, David announces that he wants to stay longer at the cabin to fish, so when Evans comes, the group tells him they plan to stay for another week. The next day, they go blueberry-picking. While the narrator picks blueberries, Joe suggests that they get married. She says no, explaining that she was married with a baby before, and it failed badly.
The following morning, Paul boats to the cabin with Malmstrom, an American who tries to buy the property from the narrator. The narrator refuses. At lunch, David praises the narrator’s decision and makes a lewd comment about her. Later, Anna informs her that David often commits adultery. Once Anna, David, and Joe leave the cabin for the afternoon, the narrator remembers she didn’t look through all the papers on the shelf. As she rifles through them, she finds a letter from a university thanking her father for his reproductions and a scholarly article about ancient rock paintings. She realizes her father’s alarming drawings were probably sketches of prehistoric art. She also recognizes one of the labels on the drawing, White Birch Lake.
Anna enters the cabin and asks the narrator what’s wrong with Joe. When the narrator explains that he proposed and she said no, Anna tells her to talk to him. The narrator finds Joe on the dock. When he demands to know whether she loves him, she offers a fumbling, noncommittal answer. He accuses her of not caring about him. The next morning in bed, they discuss which of them will move out when they return to the city.
The group travels to White Birch Lake. On the way, they see a decomposing heron that someone has hung from a branch by a rope. Once the group reaches White Birch Lake, the narrator takes David and Joe fishing, which—since they have canned food—makes her feel like an “accomplice” to murder. That night, Joe tells the narrator that he’s willing to forget about marriage and go back to how things were. The narrator refuses. The following morning, the group canoes to the cliff where the narrator’s father’s drawings suggested a rock painting would be—but there’s no painting.
Back at the cabin, David bullies an upset Anna into stripping naked so that he can film her. Anna strips and cannonballs into the lake while flipping off the camera. Afterward, the narrator canoes off to investigate another possible rock-painting location, this one underwater. She dives several times searching for the painting. On her third dive, she spies what looks like a corpse and panics. When she surfaces, terrified, Joe is there in a second canoe. The narrator, climbing into her own canoe, realizes that she faked her memories of her “husband” and “child” to avoid thinking about what really happened: her lover, a married man with children, pressured her into an illegal abortion, after which he was shocked when she broke up with him. Moreover, there are gods in nature that her father must have discovered while studying the rock paintings. The narrator canoes to land and offers her sweatshirt as an offering to the gods. Joe follows her and tries to initiate sex, but he flees when the narrator says that she could get pregnant.
The narrator returns to the cabin. Realizing that her mother must have left her an illuminating gift just like her father did, she decides to search for it. She is walking down the forest trail when David approaches and proposes sex, claiming that Joe and Anna are having sex in the woods at that very moment. The narrator tells David that she doesn’t find him attractive. He calls her a “bitch,” but when she walks away, he apologizes and asks her not to tell Anna. At dinner, the narrator flatly announces that she didn’t have sex with David, annoying Anna and David. David suggests the narrator hates men. The narrator thinks she hates all human beings.
After dinner, men arrive in a boat. David talks to them, finds the narrator, and tells her that the police have discovered her father’s drowned corpse. The narrator thinks that David is lying, but she pretends to believe him. Later, she decides her mother’s “gift” was preserving a drawing that the narrator made as a child of a pregnant woman and a horned god. The narrator goes to bed. When Joe joins her later, he smells like Anna. The narrator leads him out of the cabin, initiates sex, and thinks about the baby she’ll have, a furred god-child. Joe tells her that he loves her—sex with Anna didn’t mean anything. The next morning, the group carries their baggage to the dock and waits for Evans to arrive. While David and Joe put the first canoe back in the shed, the narrator dumps David’s film in the lake, takes the remaining canoe, and paddles away.
The narrator hides in the woods until Evans has taken Joe, David, and Anna away. She decides that she can make her parents return to her if she prays to them. The next day, she burns her own drawings and art supplies, drops her fake wedding ring in the fire, rips pages from the books in the house, and slashes all the clothes. Then she jumps in the lake, strips naked, and leaves her clothes floating there. She makes an outdoor den for herself and falls asleep in it. As the days pass, she realizes that the gods—her parents—have forbidden more and more things to her: mirrors, enclosed spaces, canned food. Eventually, she sees her mother transform into a bird and her father transform into a fish. When she wakes up the next morning, she realizes that her parents were just humans and that she needs to return to society so that she and her pregnancy can survive. She goes into the garden, sees Paul and Joe approach in a boat, and hears Joe call, “Are you there?” She realizes that she loves him, but that they still need to have a real conversation. Before going to him, she stops and listens to the natural silence.
