Gregor and the Marks of Secret

Gregor and the Marks of Secret, the fourth book in Suzanne Collins's Underland Chronicles, continues the story of twelve-year-old Gregor, a boy from New York City who has repeatedly been drawn into the Underland, a vast world miles beneath the earth's surface. This hidden realm is inhabited by giant talking animals, including bats, rats, mice, cockroaches, and spiders, as well as a civilization of pale-skinned, violet-eyed humans whose stone city, Regalia, is the seat of an ancient kingdom. Gregor has been identified as "the warrior" of Regalian prophecy, and previous quests have left him scarred and burdened with secrets.

As summer begins, Gregor's family is under strain. His mother remains in a Regalian hospital recovering from a plague. His grandmother is bedridden, his father has tremors from a past captivity, and his eight-year-old sister Lizzie has severe anxiety. Only his three-year-old sister Boots remains cheerfully oblivious. Their neighbor Mrs. Cormaci, the one outsider who knows about the Underland, holds the family together by helping with daily care and selling antiques Gregor retrieves from a Regalian museum. After Lizzie departs for camp, Gregor and Boots head underground for echolocation training with Ripred, a giant rat and fellow "rager," a term for fighters with extraordinary combat instincts.

In the training cave, Gregor encounters the Bane, the white rat he spared as a pup on a previous quest. Now eight feet tall, the Bane is emotionally volatile, speaks of becoming king, and has been influenced by a manipulative rat named Twirltongue. Ripred reveals that the Bane killed his caretaker over food and has a deeply traumatic history. After the Bane attacks Ripred and is easily defeated, Ripred tells Gregor they must kill the Bane together, citing a prophecy called "The Prophecy of Time." He warns Gregor to tell no one, especially Vikus, the elderly head of the Regalian council.

Gregor visits Nerissa, a frail royal cousin with prophetic abilities, who confirms the prophecy exists but refuses to reveal it. The next day, he arrives at the cave armed but finds it empty. In a side tunnel, Twirltongue and two companion rats corner him. Twirltongue's charming voice gets Gregor to lower his guard before she orders his death. His flashlight is smashed, plunging him into total darkness, and he panics, experiencing the vulnerability Ripred had warned about during training. He escapes by igniting an oil lamp to create a wall of fire. Vikus later relays that the Bane has run away and Ripred is hunting him.

Weeks pass. At a birthday party for Hazard, Luxa's six-year-old cousin whom she adopted after he was orphaned, Gregor takes photographs and watches traditional dances and songs that his mother recognizes from his nursery-rhyme book. He dances with Luxa, the young queen of Regalia, and realizes he thinks she is pretty. A gold crown drops from the air between them, delivered by a messenger bat. Luxa explains she gave the crown to jungle nibblers, the Underland term for mice, as a pledge to help them; its return signals danger. She fears the council will restrict her rather than act.

That night, Luxa, Gregor, and their bonded giant bats, Aurora and Ares, fly secretly to Queensland, where they find the mouse Cevian, who once saved Luxa's life, dead from a blow to the head. Beneath the body, Gregor finds a mark scratched into rock. In the jungle, the nibbler colony is deserted. The vine canopy comes alive with twisters, snakes camouflaged as vines, trapping the group. Gregor channels Ripred's spinning fighting technique to defeat them, but his rager abilities take over completely; Luxa later tells him he appeared to be smiling during the slaughter, deeply disturbing him.

Back in Regalia, a basket of baby mice is pulled from the river. Luxa convinces Gregor to investigate a nibbler colony near the Fount, a human settlement. Her cousin Howard, a young doctor-in-training, forces his way along, and Hazard, Boots, the cockroach Temp, and a young bat named Thalia also join. The Fount colony is identically deserted. Hazard spots the same mark from Cevian's body and becomes hysterical, identifying it as "the scythe," one of the "marks of secret," an ancient system of coded symbols meaning death for those who see it. Hazard's own mother died after the scythe appeared in the jungle.

Howard suggests exploring the Swag, a tunnel beneath the river, to trace the nibblers' path. An earthquake strikes while they are inside, and the river breaks through the ceiling. Boots is torn from Gregor's arms, and Hazard nearly drowns before Howard revives him. An aftershock triggers an avalanche that traps them in Hades Hall, a massive tunnel whose only remaining exit lies five days away in the Firelands. Along the way, they discover a hundred dead mice driven off a cliff by rats. Luxa recites "The Vow to the Dead," a formal Regalian oath effectively declaring war on the rats. They find one survivor, an injured mouse named Cartesian.

They emerge into the Firelands, a desolate volcanic landscape, and observe the Bane addressing hundreds of rats in a speech that falsely blames the nibblers for the plague and calls for their extermination. The group flees and encounters giant scorpions. Hazard communicates with them using fragments of multiple animal languages, and the scorpions, also displaced by rats, become allies. Nearby, Boots stumbles into a pit and discovers Ripred, emaciated and near death, his overgrown teeth locked together so he cannot eat. Luxa smashes his teeth free with her sword. Ripred reveals the Bane intends not to relocate the nibblers but to exterminate them entirely.

Approaching a volcano, the group watches in horror as the Bane's forces drive hundreds of nibblers into a pit at its base. The volcano releases invisible poisonous gas that settles into the pit. Through binoculars, Gregor watches the mice convulse and die, including pups, in a scene of mass extermination. Luxa tries to fly to their aid, but Ripred pins her down; she stabs him in the shoulder before seeing the mice are already dead.

In the aftermath, Boots innocently sings a nursery song about nibblers, mimicking their death throes as a dance. Gregor realizes the song is a prophecy that Bartholomew of Sandwich, Regalia's ancient founder, hid in a nursery rather than the prophecy room. The group decodes the rest: The volcano is the "queen" from which gold flows, and the final verse predicts a rat attack on Regalia. Nike, Howard's bat, names it "The Prophecy of Secrets."

The volcano erupts as they flee, and Thalia dies from the toxic fumes. Hazard is inconsolable. The group divides: Luxa, Howard, Ripred, and their bats will stay to find surviving nibblers and mobilize them, while Gregor returns to Regalia with Boots, Hazard, Temp, and Cartesian. Ripred tells Gregor he must retrieve Sandwich's sword from the museum, which "The Prophecy of Time" designates as his. No one will reveal the full prophecy, but their evasions convince Gregor it predicts his death or that of someone he loves.

During the flight home, Gregor and Ares pass hundreds of rats heading toward Regalia. Upon arrival, the city shows no sign of alarm. Gregor alerts the guards and sprints to the museum, where he finds Sandwich's sword and takes it up, feeling its perfect balance and the power it brings. He pockets a photograph of himself dancing with Luxa, both of them laughing. Warning trumpets blare throughout the city. The rats are coming. Vikus appears at the door, saddened, having never wanted Gregor to take the sword. Gregor tightens his grip, affirming he has found what he needs.