Quinn's mother, Karen, worked on tunneling underneath London. In 2010, Karen's crew penetrates the wall of a cavern they didn't know existed. Quinn is with the construction crew, and one of Karen's people gives him a flashlight and asks him to take a look. He is small enough that he is able to crawl inside and look around. Whether it was his touching or the noise of the drill, the Male Dragon, which had been hibernating inside, woke up.
He spits the flammable liquids it uses to generate flame in Quinn's eyes, and Quinn quickly flees. His mother finds him and Quinn tells her rapidly and repeatedly, "there's something in there". Karen is too busy looking at the damage to his eyes to pay much attention. After washing out his eyes fails, she takes him over to the elevator to take him to the surface so he can get medical attention.
As they are getting into the elevator, the male dragon kills Karen's crew with a burst of flame and a roar. Karen and Quinn get into the elevator and start going up, but slowly. Karen is desperate to get to the surface as flame billows up from the base of the tunnel into the shaft.
Midway up the shaft, the male dragon climbs out from the flame underneath onto the shaft. Karen is crushed to death when he puts a claw on the shaft. Upon hearing Quinn's screams, he looks inside at him, but decides to leave him alive and flies outside to feed. A newspaper article later revealed that Quinn is the only survivor.
It is ten years after the male dragon awoke. Humanity is losing and the dragons, having burned much of the world to ash, are starving and more dangerous then ever. Quinn is now the leader of a colony of humans that live inside the ruins of Bamburgh castle. At this point, Quinn has adopted an orphan named Jared.
The starving survivors wait for the crops to ripen. Most trust him, but some grow restless in their wait. An especially defiant group of survivors, Eddie Stax, with his teenage children Rachel, Devon, Michael, and Matt, steal a truck to pick tomatoes while Quinn sleeps. Attacked by a female dragon during the secret raid, Eddie loses Matt, with Michael being badly burnt. Quinn and his best friend Creedy step in to rescue the remaining survivors with old fire engines. Devon boards the first truck, manning a water cannon. As Creedy leads the way out of the fields to escape, the dragon appears in front of them, blocking the exit. She sets both trucks ablaze, immolating Devon and stalling Creedy’s truck. As tensions mount, Creedy manages to bring his truck back to life, and pushes the rescue party backwards and out of harms way. The dragon lets them leave, more interested in the ashes of the burning field.
The Kentucky Irregulars, a group of Americans led by Denton Van Zan, arrive at Quinn's castle with a Chieftain tank and an Agusta Westland AW109 utility helicopter, the latter of which is piloted by Alex Jensen. The female dragon that destroyed the crops attacks the castle, and Quinn watches as Van Zan's people spread out to hunt the dragon. When the mission goes awry, Quinn acts as bait to lure the dragon to Van Zan, and the dragon is subsequently killed.
Van Zan and Alex tell Quinn that all the dragons they have killed are female and that there is likely only one male. If they can kill it, they can end the species. Quinn fears agitating the Bull Dragon will be a suicide mission, as well as dooming the survivors in his care. He recounts a nearby fortress of survivors in Pembury heading to London, only to be backtracked and totallydestroyed by the ferocious dragon. When pressed by Alex, he admits to having seen the Bull dragon first hand, when it killed his mother in his youth.
Van Zan's attack force is wiped out by the male dragon in the ruins of Pembury, 66 miles from London. The dragon then backtracks them to Bamburgh castle as Quinn feared. Many of the survivors are killed, the castle ablaze. Quinn rushes to get the remainder to the underground bunker. As survivors scream and plead for help, Creedy rushes back into the flames to save them. At this point the bull dragon returns to finish the inhabitants of the castle, pumping a horrendous fireball into the innards of the castle. As the fire twists and winds through every corridor, Creedy turns to retreat back into the bunker, only to be engulfed by the flames which in turn, force the bunker door closed. Alex, Van Zan and two surviving irregulars return to the castle and dig the survivors out from the bunker. After seeing his castle in burned-out ruins, Quinn decides to help them kill the male. Jared is left in charge of the survivors from the attack, mostly children.
The three of them fly to London in Alex's chopper. Once there, they see the male dragon cannibalizing females, warding most of the dragons away from the city. Using Quinn's knowledge of the tunnel system, they infiltrate the city. Van Zan organizes a plan to shoot explosive crossbow bolts down the bull dragon's throat, but needs to be dangerously close to the dragon to pull off a successful shot. He hands off one bolt to each of their party, separating to spring his trap. Van Zan attempts to shoot the male from atop an old smokestack, but is subsequently killed by the dragon. Quinn and Alex lure the bull dragon to ground level and Quinn fires into his mouth, killing the male.
Later, Quinn and Alex erect a radio tower on a hill overlooking the North Sea. Jared arrives to say they have contacted a group of French survivors who want to speak to their leader. Quinn tells Jared he is now their leader and dedicates himself to rebuilding. There have been no dragon sighting for over three months, and Quinn views the idea of them returning remote.
He says that if they ever return, "They'll burn. We'll build. Maybe I'll just kill 'em".