Exodus is the decades-long story of the birth of Israel as an independent nation in 1948. The book opens with the reunion of American war correspondent Mark Parker and his childhood friend Kitty Fremont. Kitty is a nurse working with Greek orphans on Cyprus shortly after World War II, and Mark is on his way to Palestine to cover the tense events unfolding there. The two are joined one night at dinner by Ari Ben Canaan, a Palestinian Jewish man who needs Mark’s help making headlines and Kitty’s nursing skills. Ari works with Mossad Aliyah Bet, a Jewish organization that facilitates the escape of immigrants into Palestine. The British forces that occupy Palestine are severely limiting Jewish immigration, and Ari wants to stage an escape from internment camps on Cyprus to force the British to change their restrictive policies. As opposed to typical escape runs, Ari is planning a very public escape of three hundred Jewish children from Caraolos detainment camp.  

Kitty is not interested in the job offer to be a nurse at Caraolos, but she is drawn to the mysterious Ari. She goes to see the camp so that she can refuse the job and get the idea out of her system. The refugees at the camp, most of whom have been in concentration camps during World War II, are being detained in Cyprus until the Palestine mandate is decided. While she is taking a tour of the camp, Kitty meets a young girl, Karen Hansen Clement, who reminds her of her deceased daughter. Kitty decides to take the job at the camp to be close to Karen. Soon after, she surprises herself by deciding to follow Karen to Palestine because the girl will be one of Ari’s refugees. Meanwhile, Brigadier Bruce Sutherland is the British miliary commander in Cyprus. He is unique among his colleagues because he has sympathies for the Jewish people who want to be in Palestine. The sympathies of the British government, on the other hand, are with the Palestinian Arabs, because of the tremendous amounts of oil in the Middle East.  

Ari and his friends Zev, David, and Joab, all members of the secret Jewish army, the Palmach, carry out the preparations for the escape with precision and efficiency. Dov, a teenage boy who survived Auschwitz, provides excellent forgeries that Ari needs to acquire weapons and supplies and to get the children out of Caraolos. Ari is a skilled strategist who can anticipate the actions of his enemy. He asks Mark to file a news story about the escape attempt as soon as the three hundred children have boarded the ship, Exodus, during broad daylight. He wants international attention on the mission. By the time the British realize that an escape attempt is occurring, it is too late. There is a standoff that lasts for days, the children on board Exodus, and the British, watching helplessly as the world forms its opinions. Finally, after days of dangerous hunger strikes and threats of suicide, British Major Cecil Bradshaw decides to allow Exodus to sail to Palestine.  

The children arrive in Palestine, a lush place full of thriving communal kibbutzes and villages. The farms were established a generation earlier through the determination and hard work of Ari’s father Barak, his uncle Akiva, and their fellow Palestinian immigrants. Barak and Akiva, originally Jossi and Yakov Rabinsky, grew up in the Jewish Pale in Russia and fled their home when Akiva killed a man to avenge his father’s death. When the brothers arrive in Palestine, they find it barren. Along with other immigrants, they build settlements. The brothers get married and have children. The Hebrew language is revived, and the brothers choose their Hebrew names, Barak Ben Canaan and Akiva. When violence erupts between the Jewish people and the Palestinian Arabs, Barak and Akiva form a military. The measured and contemplative Barak chooses restraint in their interactions with the Arabs, but Akiva chooses action. After his wife and child are killed, Akiva leaves the settlements to form a guerilla military called the Maccabees. Barak feels Akiva is wrong for pitting Jewish people against each other and tells Akiva he never wants to see him again. Meanwhile, Barak has become an important and trusted diplomatic figure, joining the Zion Settlement Society and Yishuv Central, the democratic government of the farming settlements.  

When Ari is old enough, he joins the Palmach, the striking arm of the secret Jewish army called Haganah. He also becomes involved with Mossad missions, his first being in Berlin, where he helps desperate Jewish people obtain visas on the eve of World War II. Ari also loses Dafna, the girl he loves, in the ubiquitous violence of Palestine and becomes hardened by a life of defending his land. Like many of his fellow Jewish people, he hates the British for their oppressive and unjust occupation of Palestine. When Exodus arrives safely in Palestine, Ari helps Kitty get a position as a nurse at the Gan Dafna village, named for Ari’s Dafna, where Karen will live. Kitty and Ari are attracted to each other, but do not act on their feelings. Although Kitty always feels like an outsider in Palestine, she is an efficient and respected addition to life at Gan Dafna.  

Over time, Kitty starts to see the Jewish people as strong and fiercely proud of their homeland. Still, she is determined to bring Karen to America. Dov is an obstacle to this goal because Karen and he have grown close. Karen is essentially the only person with whom the detached and melancholy Dov interacts. When Kitty gets word that Karen’s father is alive, she brings Karen to see him. He is the only surviving member of her family after the war, and he has had a mental breakdown. The visit crushes Karen. Dov hears of Karen’s ordeal and leaves Gan Dafna because he does not want to stand in the way of Karen’s happiness in America. Dov joins the Maccabees and he and Akiva are soon captured by the British and imprisoned for their part in attacks targeting British officers. Ari plans a daring escape, during which hundreds of other inmates are freed. Akiva is shot and dies before Ari can tell him that Barak has forgiven him. Dov survives the escape, returns to Gan Dafna, and professes his love for Karen.  

As violence between the Jewish and Arab people intensifies, the British do little to help the Jewish people. Barak asks Ari to visit his old friend Taha, son of Barak’s friend Kammal. Years earlier, Barak helped his Arab friend Kammal establish a joint kibbutz, Yad El, where Arab people were taught the ways of Jewish farming and the children were formally educated. The experiment was a great success and there were many years of friendship at Yad El. Now Taha is passively helping hostile Arab people who use his village, Abu Yesha, to get closer to the Jewish settlements they intend to destroy. When Ari confronts Taha, Taha makes no promises to stop the Arab people and Ari is disappointed by the shocking lack of loyalty his old friend shows. The British military try to find a solution to the tension between the Palestinian Arabs and Jewish people. The Arab people refuse to negotiate, and the Maccabees complicate the situation with their ruthless acts of terror. More immigrants are being smuggled illegally to Palestine, making the British look impotent. Ultimately, it is decided that the situation will be turned over the United Nations.  

In November of 1947, Barak spends time in Geneva gathering votes for the Palestinian partition. After several suspenseful days and a mock vote that is lost by the Jewish side, the UN votes in favor of partitioning Palestine in a two-state solution. The Arab people in the book vow to destroy their Jewish neighbors and declare a holy war. The Jewish people, with fewer weapons and fewer men, suffer some defeats but also win many decisive victories that shock military strategists all over the world. The children of Gan Dafna must be smuggled out of their village before a brutal attack, which Ari and his soldiers successfully repel. During the fighting, Ari loses all of his closest friends and must take the village of Abu Yesha where his friend Taha lives. In May of 1948, the State of Israel is declared independent, though the fighting continues. 

In the last section of the book, immigrants from all over the world flood into Israel. Ari lives in the Negev Desert for two years forming an elite military group, and Kitty, who decides to remain in Palestine, works with new immigrants. Barak, now eighty-five years old, learns he has cancer. After apologizing to Ari for inadvertently creating a generation of unemotional warriors, Barak dies and is buried near his brother. Dov visits Karen with the news that he has the opportunity to attend the Massachusetts Institute of Technology in America. Karen tells him she cannot possibly go with him, as she is needed in the new border settlement of Nahal Midbar. When they see each other for Passover at Sarah Ben Canaan’s cottage, Kitty promises Dov that they will convince Karen to go to America. When Karen is late in arriving for Passover, Ari goes to learn of her whereabouts and returns with news that Karen has been killed. Kitty is overcome with grief. Dov refuses to hate Karen’s murderers, because Karen could never bring herself to hate anyone. Ari isolates himself from the group, and after Kitty collects herself, she goes to see him. He finally shows the emotion that Kitty has wanted him to express for years. They return to the others in the cottage, Kitty knowing that she will always come second to Israel in Ari’s heart. Sutherland leads the Passover Seder and the group commemorates how the ancient Israelis went forth in triumph from slavery into freedom.