Book 1: Beginnings
We begin during the rule of Bharata, when everyone on Earth follows dharma. His lineage is traced to two sons: Dhrtarastra, who is blind and cannot inherit the throne, and Pandu, who becomes king. Pandu has one illegitimate son he must give up to be raised as a Suta and five sons to call his own, and all six are gods incarnate. Dhrtarastra has 100 sons (called Kauravas), all demons. Pandu's five sons Arjuna, Bhima, Yudhisthira, Nakula, and Sahadeva are all great warriors or great kings, and marry the princess Draupadi. Dhrtarastra's son Duryodhana leads the other 99 brothers, and has a seething hatred for the Pandavas, or Pandu's sons. Both Yudhisthira and Duryodhana are granted kingdoms by Dhrtarastra.
Book 2: The Hall
After Yudhisthira is consecrated as king, Duryodhana schemes to take his kingdom. So, Duryodhana challenges Yudhisthira to a dice game. Duryodhana implores Yudhisthira to participate, and Yudhisthira determines that it's his dharma to play despite being a terrible gambler. He gradually gambles away his entire kingdom and the freedom of his wife, but Dhrtarastra commands Duryodhana to give Yudhisthira one more change. Duryodhana agrees, saying that if Yudhisthira loses he and the other Pandavas must live in exile for 12 years and spend a 13th year in disguise, and if they're recognized, they must spend another 12 years in exile. Yudhisthira loses.
Book 3: The Forest
The brothers and Draupadi spend the 12 years of exile in the forest, studying with Brahmins and training. During this period of time, Arjuna is granted a celestial weapon by the god Indra. Draupadi is kidnapped and brought back.
Book 4: Virata
During their 13th year, the Pandavas take refuge in the king Virata's palace, posing as former subjects of Yudhisthira. Draupadi poses as a maidservant to maintain her independence. It's an eventful year, with a rape attempt on Draupadi that leads to Bhima slaughtering all of the aggressor's supporters and Arjuna helping Virata's son win back cattle from thieves. The brothers make it through the 13th year undetected despite these showy adventures.
Book 5: Perseverance
Yudhisthira returns to take his kingdom back, but learns Duryodhana has no intention of turning it over. Duryodhana clearly wants war, but Krsna advises Yudhisthira to ask for a peaceful transfer of power first. Duryodhana denies this peaceful transfer, clearly desiring war despite being chided by everyone close to him. The two sides prepare for war. Duryodhana appoints Bhima his commander. Krsna tells the Yudhisthira that even though he will equip Duryodhana with soldiers, he will side with the Pandavas.
Book 6: Bhisma
At the beginning of the battle, Arjuna asks Krsna for permission to throw down his arms since he does not want to slay his kind. Krsna recites the Bhagavad Gita to Arjuna, explaining the tenets of dharma and action, and specifically Arjuna's duty to fight in this war with a preordained outcome. After a sustained conflict between Arjuna and Krsna, Arjuna finally kills Bhisma on the 10th day of the war, and Bhisma chooses to lay on a bed of arrows and delay the date of his death.
Book 7: Drona
Drona, Arjuna's former military trainer, is appointed the new commander of Duryodhana's army. He is a fearsome fighter, so the Pandavas devise a plan to trick Drona into defying his dharma, making himself ready to die. Yudhisthira tells Drona that Bhima killed Asvatthaman, which is the name of Drona's son. In reality, Bhima killed an elephant named Asvatthaman. Drona flies into a fit of rage and violates his dharma by massacring soldiers he shouldn't kill. When he realizes what has happened, he lays down his arms and accepts his death.
Book 8: Karna
Duryodhana begins to grasp that his campaign is doomed, but at Karna's request, he appoints Karna the new commander of his army. Karna and Arjuna meet on the battlefield in a bloody exchange, in which Karna is slowly brutalized and killed.
Book 9: Salya
Salya is appointed the next and, ultimately, final commander of Duryodhana's army. He is quickly killed by Yudhisthira. Duryodhana flees to hide in a lake, knowing the end of the war is imminent, but the Pandavas find him. Bhima kills him in a match with clubs, using an unfair strike. Despite the protests of observers and Duryodhana himself, Krsna ordains the strike, saying it was within Bhima's dharma and that Duryodhana had acted in adharma by instigating the war.
Book 10: The Night-Raid
Among the handful of Kauravas surviving, Asvatthaman sneaks into the Pandavas' camp and massacres everyone in it, some of them in such a way that they do not die a proper warrior's death and can't attain heaven. As he leaves, he places a curse on Pandava wombs, making them barren.
Book 11: The Women
Yudhisthira visits Dhrtarastra, who is mourning over the death of all of his sons. Likewise, the Kauravas' wives confront Yudhisthira about massacring their husbands. When Dhrtarastra sees Bhima, he tries to kill him, but Krsna tricks Dhrtarastra into attacking an effigy of Bhima instead. There is a funeral pyre for the Kauravas and then a ritual at the Ganga river. At the Ganga, Yudhisthira learns that Karna was his brother, and plunges into grief.
Book 12: Tranquility
Yudhisthira is ambivalent about taking his throne, but agrees to it to honor Dhrtarastra. The Pandavas travel to visit the dying Bhisma, who asks for a pillow from Arjuna, but means that he wants more arrows to rest his head on. Bhisma begins a philosophical conversation with Yudhisthira on his duties as a king and the nature of dharma.
Book 13: Instruction
Bhisma's and Yudhisthira's conversation continues, as they talk about how to live well and abide by dharma, as well as about women. Bhisma tells Duryodhana that he should consider the Pandavas his own sons, and forget about his wicked sons that have gone to hell. Bhisma dies and is cremated.
Book 14: The Horse Sacrifice
Yudhisthira hesitates to resume ruling, but Krsna instructs him to undertake a horse sacrifice ritual to cleanse the world. Arjuna rides the white horse that will be sacrificed around the former sites of battle and fends off various aggressors. After the journey, the horse and many other animals are sacrificed in a pyre, and the smoke from the horse's burning intestinal sac does the purifying.
Book 15: The Hermitage
Dhrtarastra and his wife Gandhari, along with the Pandavas' mother Kunti and some others, retreat to a forest hermitage to live out their days as ascetics. The Pandavas miss their mother sorely and organize a trip to visit the elders. Shortly after their trip, their elders burn to death in a sacred fire lit by Dhrtarastra.
Book 16: The Clubs
We read the tale of the Vrsni who descend into sin when they learn of their demise by time. Krsna is himself killed by a hunter named Jara, which is Sanskrit for "old age." He ascends and rejoins the gods. Without Krsna, Arjuna is unable to defend the Vrsni women from a kidnapping by a pack of thieves. He returns to tell his brothers of his defeat.
Book 17: The Great Journey
With Krsna dead, Yudhisthira decides it is his time to die as well. He leaves the throne to Pariksit, and he and his brothers set out on a journey to travel the world. In the mountains, the brothers and Draupadi die one by one. When Yudhisthira is met by Indra to be taken in a chariot to heaven, Yudhisthira refuses to leave his dog behind, since it was loyal to him. The dog transforms into the god of dharma and praises Yudhisthira for his virtuousness.
Book 18: The Ascent to Heaven
Yudhisthira only finds Duryodhana in heaven and is baffled. He demands to be taken to where his brothers are, so he is taken to hell. There, Yudhisthira says he will stay with his brothers instead of choosing to go to heaven. Indra informs him that this was the final test that he passed, and he and all the Pandavas are sent to heaven, while Duryodhana is condemned to hell.