The novel begins as the brothers Hermes (the Greek messenger god of thieves, travel, translation, etc.) and Apollo (the Greek god of light, poetry, medicine, etc.) enjoy some time on Earth, specifically in a Toronto tavern called The Wheat Sheaf. The guests around them are awestruck and "worship" the gods: for example, while one man touches Apollo sexually in the bathroom, another offers to pay for their drinks (13-14). The gods themselves, however, are having a disagreement. Hermes, the more earthly of the two, believes that there is something special and amusing about human behavior while Apollo believes humans to be no different than any other creature on earth. To settle a bet about the nature of humanity, each brother wagers a year of servitude to the other over a question central to their debate—would any animal, given human intelligence, "be even more unhappy than humans?" (14). Hermes refines this bet by saying that, if even one of the animals dies happy, he shall win the bet. Apollo initially protests, but later agrees to these terms. Since they happen to be by a veterinary clinic when the wager is made, they select the fifteen dogs in the clinic as subjects and, leaving them with their memories, bestow human intelligence upon them.
A German Shepherd in the clinic named Rosie is the first to suddenly gain consciousness. She immediately recalls memories of her lost litters and notes that her food bowl has suddenly taken on a pink hue that she, until now, was never able to perceive. Next, a Neapolitan Mastiff named Atticus wakes from a dream of chasing squirrels when he bites down on a squirrel's neck and realizes that it must feel pain. Slowly, each dog in the kennel becomes aware of their change or wakes from sleep into this awareness. A black Poodle named Majnoun contemplates the lock on Rosie's cage and eventually figures out how to open it and free her. As the other dogs learn to do the same, we are then introduced to "two Labrador yearlings who had been left overnight for neutering" named Frick and Frack, "a chocolate teacup poodle" named Athena, a Schnauzer named Dougie, a Beagle named Benjy, and an old Labradoodle named Agatha. The dogs then start to invent a new language using their newfound faculties, different entirely from their simple and initial dog language. They then escape by the back door and contemplate their next move.
We are told here that this is where the journey ends for three of the fifteen dogs. Agatha, being so old, feels she has led a good enough life already and decides to stay at the clinic and await her mistress. She does not know that, in reality, she has been left there by her mistress to be euthanized, and the next day, when the staff find her out of her cage, they are cruel to her and hurt her as they euthanize her. She dies thinking of her mistress. Ronaldhino, a mutt, returns home to his masters, but he is disillusioned by his newfound realization of their condescensions toward him. He dies bitter and disillusioned with such condescension. Another mutt, Lydia, becomes very nervous with her newfound awareness of the passage of time, and her stress when her masters are gone for long periods causes her to develop catatonia. Later, she is euthanized at the same veterinary clinic where she gained the capacity for intelligence.
The perspective then shifts to the other dogs, who are reasoning out where they ought to go next. The smells of the lake draw them in, but Majnoun is skeptical of the choice to head toward the lake, where they might encounter other, dangerous dogs. We are introduced to others among the pack, including a mutt named Prince, a Duck Toller named Bobbie, Bella the Great Dane, and a mutt named Max. While Atticus suggests that the pack hunts, Majnoun submits that they ought to find a hiding place in case a master (i.e., a human) happens upon them. Each dog then thinks about their position on submission to a master: while some dogs like Athena depended on their masters for transportation and more, others like Majnoun resent the rituals of submission but enjoy the feeling of being rewarded or treated by a master. Ultimately, once many of the dogs realize that they would not bite their masters, they decide to seek shelter. First, however, they hunt. After hunting for a few days, their new language starts to deepen and grows more complex, particularly through the efforts of Prince, who invents words and puns. Their hunting habits also become more complex, and they develop nineteen units with which to break up day and night. They also, in thinking about time and place differently, begin to construct a den in a coppice.
Another innovation discussed at length is the decision by Bella to carry the much smaller Athena on her back to conserve energy. This brings the two dogs closer together but also attracts the attention of some abusive humans, who throw rocks at them. Bella savagely attacks the leader of these abusive humans, and Atticus and Majnoun run in to assist Bella with the others. This leads to Bella and Athena being more scrupulous in their scavenging and remaining closer to the coppice. A short interjection about the unpredictability and emotional vacillations of humans is offered. We are then told of how other dogs react to the pack—namely, with fear and aggression, even towards the smallest dogs in the pack that are not physically intimidating. This idea, that they are not entirely dogs anymore but are dogs at heart, is deeply troubling to Atticus, Rosie, Prince, and Majnoun. Prince and Majnoun, however, would not give their newfound intelligence up to return to ordinary life, unlike Atticus, Rosie, and the others.
Max, Frick, and Frack, on the other hand, learn to suppress their thoughtfulness and only crave dominance or submission. They are very aggravated by Prince because the status and reverence he earns through words is unfamiliar to them. When Prince begins to recite poetry, which the three think is an awful and meaningless abuse of their new language, Max attacks Prince and is stopped only by a forceful intervention from Majnoun. However, Atticus tells Majnoun not to kill Max, since it would be bad to murder one of their own, and he assents. The others are left to think about how words could cause a fight between two animals, when before all that would have started a fight is a clash over dominance.
Two nights later, Atticus approaches Majnoun. Majnoun expects this approach because he has been thinking about the group's lack of leadership and knows it to be an unnatural situation. Though Majnoun thinks that he is able to understand the thought behind human speech, he does not want to lead. He understands, nonetheless, how such a strange change in thinking and behavior means that a simple physical struggle for dominance will no longer suffice to pick a leader. Atticus tests the waters with Majnoun and asks if he thinks that they should try their best to fit in with other dogs and act as they used to. While Atticus is resolute that the other dogs can teach them how to fit in again with the collective, Majnoun disagrees and insists that the new thinking is a gift, one that they might even teach other dogs. Having reached an impasse, Atticus asks Majnoun whether he would challenge him if he assumed control of the pack. Majnoun says that he would not.
The next day, while other dogs are scavenging, Atticus meets with Max, Frick, and Frack. They are a faction that wants to force the pack to revert to their old ways, and they realize that, in order to do so, they will have to kill Majnoun and exile/kill the others who are in alliance with him—Athena, Bella, and Prince. They organize a plan and, when the others are just getting to sleep in the den, set it into motion. Frick picks up Athena in his jaws, kills her, and makes off with her. Frack then wakes Bella and says that Athena has gone missing, with Frick having gone off to find her. They lead Bella to a busy street and tell her Athena is on the other side. Bella is struck dead trying to cross the road by a car. When Frick and Frack return to murder Prince, however, they find that the mass they thought to be his body is no more than a pile of human clothes.
The scene then changes to Apollo and Hermes, who have been watching the entire time. While Hermes argues that Bella and Athena died happy because of their mutual friendship, Apollo insists that at the moment of death, neither was happy but rather confused and in pain. Apollo offers to let Hermes intervene if the wager is doubled, and Hermes assents. Hermes then appears to Prince in a dream as a black dog with a blue patch on his chest. He tells Prince that he is in danger and of the murders of Athena and Bella. He helps Prince escape invisibly using his godly power and, once Prince is far away from the others, he flees and begins his exile from the pack.
Meanwhile, Atticus is with Majnoun at a pond near the coppice. Atticus regrets that he will have to kill Majnoun because he understands Majnoun's way of thinking. They are discussing the nature of belonging when suddenly, the other conspirators (Max, Frick, and Frack) run up and announce that Bella has been killed by a pack of dogs. They all run toward the coppice to assist Bella, but when Majnoun and the conspirators are not far from the coppice, the conspirators turn on him, attacking him brutally and leaving him for dead.
This first chapter is particularly important for the way that it situates readers fully in the realm of the apologue (i.e., an allegorical narrative or moral fable that usually features animals as characters). For example, we open on the two gods discussing the nature of humanity because—even though the novel is named for the central fifteen canines—it is really a tale about the nature of humans and the ways we think. This allegory between dogs and mankind is central, and it is cemented both throughout the novel and before the novel even begins. For example, when the book provides us with the brief "Dramatis Canis" list, it not only situates us firmly in the atmosphere of Greek theater or tragedy, but also calls our attention to the person-like quality of the dogs by drawing an obvious comparison to the dramatis personae that usually opens plays. Moreover, Apollo's joke that humans are no more interesting than flies or frogs may be an allusion to both Aristophanes's play The Frogs and Jean-Paul Sartre's play The Flies, itself a modern-day reinterpretation of the Orestia.
The basic drives of the dogs, once endowed with human intelligence, are also deeply symbolic of the essential human drives. For example, Majnoun is the first to attend to a basic human desire when he, thirsting for freedom, opens the cages of the other dogs. The fact that he is capable of doing so but did not think to do so until endowed with human thought reinforces the idea that some craving for freedom is intrinsic to the human condition or human cognition. The next drive of theirs, towards language and communication, is representative of the human drive towards community, belonging, and kinship—a theme that will go on to be discussed at length throughout the book. Later in the chapter, the dogs will also explore a range of human desires both basic and complex—for shelter (i.e., what drives them to the coppice), for leadership (i.e., what leads them to appoint Atticus as the head of the pack), for security (i.e., what leads them to attack other humans and other dogs on each other's behalf), for justice (i.e., what drives them to establish a hierarchical system of rights and privileges based on status within the pack), and even for art (i.e., what leads Prince to innovate with language in the form of puns and poems). Even so, however, one does well to recall that the central dispute which breaks up the pack by the end of Chapter 1—whether or not the pack should try and return to their old ways and thus the larger community of dogs—is fundamentally one based on belonging and relationships. Belonging is thus depicted as a central aspect of the human experience.
The centrality of belonging—both to the pack and within other systems—is thoroughly emphasized in many places in this first chapter. For example, though five dogs are dead by the end of the chapter, we are cued by the title to only think of the pack as it was when it was whole, as the titular Fifteen Dogs. In the text, when the dogs are crossing a major road on their way to the lake, there is foreshadowing in how Rosie, Athena, Benjy, Prince, and Bobby wait with Majnoun, while the others go with Atticus (20). In fact, save Rosie, these dogs that wait with Majnoun will all be labeled as dissenters and killed in due time. This is not only an element of foreshadowing, however: it is also a subtle clue that the animals are already thinking with complex intuition early on, even before their language grows complex or their understanding of time is cemented. Those who eventually side with Majnoun—either by force or by will—are already doing so, and the same is true of Atticus' followers. Moreover, much of Chapter 1 seeks to grapple with the experience of the dogs as defined by the smaller groups within the pack to which they belong. The lengthy interlude about Bella and Athena, for example, cements them as a small sub-faction to account for, even in the gods' eyes (note how Hermes appeals to this bond to argue with Apollo about their happiness at death). The various references to the conspirators as a group throughout the chapter (i.e., as "Max, Frick, and Frack), even before they make a plan together, also cements their cohesion as a faction.
Two other important and clear textual clues about the importance of belonging come in conversations that the dogs themselves have with others. When Prince talks with Hermes in his dream, for example, Prince's initial and chief concern is the pack to which he belongs: "But what am I without those who understand me?" (37). His concern is the language that he has created with others, as well as those others who would understand him, rather than his life; he must be persuaded by Hermes that the opposite prioritization is correct. Second, when Atticus is stalling Majnoun by the pond while waiting for the other conspirators, they are also speaking of the importance of belonging to a larger collective: "can there be a feeling greater than belonging?" (39). This is, of course, a grand irony to the text: in the name of belonging to a larger collective, the dogs have gradually become more and more selfish, even to the point where they are prepared to kill others of their kind in service of vague ideals.
One final element to keep track of—both within the first chapter and elsewhere—that foregrounds the theme of belonging among the dogs is that of Prince's poetry. As Alexis tells us in the novel's postscript, "In each poem, the name of a dog will be audible—to the listener or to the dog—if the poem is said aloud, though the name is not legible." For example, in Prince's first poem, the name Majnoun appears in the last line as a union of the words "Madge" and "noon" (28). In his second poem, note how Bella's name appears in the third line within the phrase "bell and bones" (29). Prince's final poem in the chapter contains Rosie's name in the last line between "rose" and "even" (34). The fact that Prince's language, either intentionally or unintentionally, comes to incorporate the names of his pack mates suggests an inextricable link between the community of dogs and the language that they use. Even if the language is banned (as it later is) or is used for treacherous purposes, it bears traces of its inventors. This is especially interesting to keep track of later in the novel when we see how the community of dogs in the pack further fractures and how other dogs find community among humans.