In Budapest, amid the gunfire of the 1956 uprising, Gregor Vassy calmly tells his young daughter, Florence, THE STORY OF CHESS. As he finishes, Florence is taken away to escape the war-torn country, leaving him behind to fight the Russians.

The sounds of rebellion give way to the furor of a press converence in present-day Bangkok, where the first half of the World Chess Championship is about to be played. The temperamental American chess champion, Freddie Trumper, arrives with Florence, his second, and immediately alienates both the press and his Russian opponents, Anatoly Sergievsky, and his second, Ivan Molokov.

Back in his hotel room, Anatoly is told by Molokov that he must play one game with their Ambassador. He ponders who he is, what is expected of him and whether or not it's worth it (WHERE I WANT TO BE).

Florence has become increasingly frustrated by Freddie's cheap theatrics and the crass commercialism of his agent, Walter. She asks herself why she should endure such abuse (HOW MANY WOMEN).

Prior to the commencement of the Championship, the Arbiter and the merchandisers sponsoring the event all join in singing the CHESS HYMN. During the first game, Freddie, accusing Anatoly of cheating, creates a scene and storms out of the arena, leaving Florence, the Arbiter, Molokov, and Anatoly to find a way to resume the game (QUARTET).

Later, in his hotel room, Freddie berates Florence for cooperating with the Soviets. Warning him that she has had enough, she tells him they are expected to meet with Anatoly and Molokov that night. He will have none of it (YOU WANT TO LOSE YOUR ONLY FRIEND?) and leaves Florence alone to consider her situation (SOMEONE ELSE'S STORY). Shadowed discreetly by Walter, Freddie explores the seamier side of the local nightlife (ONE NIGHT IN BANGKOK).

Florence joins Molokov and Anatoly at the restaurant, but Freddie is nowhere to be found. Frustrated, Molokov leaves to see if his men can find him. Left alone, Florence and Anatoly, against their better judgement, find they are attracted to one another (TERRACE DUET). Freddie bursts in on them and is infuriated at the sight of them kissing.

It is a few days later. Freddie, still burning from what he sees as Florence's betrayal of both him and the memory of her father, is losing the match. When Florence offers some constructive criticism he orders her to get out. Her confusion gives way to anger and resolve as she packs her bags to leave Bangkok and Freddie (NOBODY'S SIDE).

In the underground garage of the arena Florence is given a letter from Anatoly by Walter (who, as she had suspected, works for the C.I.A.) stating that Anatoly, in spite of the fact that he is married, wishes to defect because he loves her. Together Anatoly and Florence escape. Upon their arrival at the airport they are faced by members of the press, who question Anatoly's reasons for defecting. He answers them with his stirring ANTHEM.

Two months later, the second half of the World Chess Championship is about to take place in Budapest. the timing of the match coincides with a summit meeting between the United States and the Soviet Union. In the spirit of glasnost, the Soviets have allowed the defector Anatoly to return behind the Iron Curtain to play chess as an American. While a choral group practices for the summit (HUNGARIAN FOLK SONG) Anatoly asks Florence how it feels to be in Budapest after so many years away. She confesses sadly that although it is her homeland, she has no memory of it; she has only the address of what was once her home and the faint hope that her father may still be alive.

Florence encounters Molokov in a church, where he offers to help find her father or at least to find out what became of him. Florence considers the changes she has made in her life over the past two months (HEAVEN HELP MY HEART).

At the hotel Freddie becomes furious with Walter when he discovers that Florence and Anatoly are staying there also. Walter gets Freddie to channel his anger into shaping up for the match (NO CONTEST).

Florence learns that Anatoly's wife, Svetlana, is in Budapest. Anatoly allays her fears, assuring her of his love. Later, he visits Svetlana at her hotel. He is torn between love for Florence and compassion for his wife (YOU AND I). Molokov tells Anatoly of the hardships that are being imposed upon Svetlana and other members of his family who are left to suffer the shame of his defection.

At the match Freddie is beating an emotionally torn Anatoly. Outside of the arena Walter and Molokov discover that at times opposing sides can help each other out. The Soviets would like Anatoly back. What can they offer in return? Molokov gives Walter an envelope with information about Florence's father. Perhaps some sort of trade can be arranged? Walter is only too eager to help.

At dinner, Anatoly tells Walter and Florence he is exhausted and needs a week to rest. Florence doubts that Freddie would consent but agrees to try to convince him. Svetlana and Molokov enter the restaurant. After they are introduced, an embarrassed Florence asks to be excused. Svetlana finds her on the terrace. They discover they share a great deal in common. Both of them seem destined to lose the man they love (I KNOW HIM SO WELL).

Interrupting a television interview, Florence asks Freddie for the break in the match. He spitefully refuses, and she leaves. In front of the hot lights of the cameras, Freddie breaks down and reveals what has made him the turbulent soul that he is (PITY THE CHILD).

Thanks to Molokov, Florence is taken through the winding streets of Budapest to meet a man who might be her father. When he sings her a tender LULLABY, she is sure of it.

The exhausted and confused Anatoly is the subject of speculation by the K.G.B., the Arbiter, the C.I.A., the press and the merchandisers. Anatoly enters the arena and begins to play. At the height of the match, deciding to accept the K.G.B. offer to return to Russia so that Florence may be reunited with her father, he knowingly makes a wrong move--and Freddie is the victor (ENDGAME).

At the airport, Florence has a tearful goodbye with Anatoly (YOU AND I). Once he is gone, she is told that the man she met was not her father after all. Instead, Anatoly had been traded for a captured C.I.A. agent. Betrayed by her own country, having lost both her father and the man she loves, Florence is left alone to face whatever the future may bring.