A French Intelligence Agent becomes embroiled in the Cold War politics first with uncovering the events leading up to the 1962 Cuban Missile Crisis, and then back to France to break up an international Russian spy ring.
A high ranking Russian official defects to the U.S., where he is interviewed by U.S. Agent Michael Nordstrom. The defector reveals that a French spy ring codenamed "Topaz" has been passing N.A.T.O. secrets to the Russians. Michael calls in his French friend and counterpart Andre Devereaux to expose the spies.
1962. While vacationing in Copenhagen, Denmark, K.G.B. official Boris Kusenov, his wife, and their daughter are able to defect to the west with arranged assistance from the U.S. authorities, the operation led by C.I.A. Agent Mike Nordstrom, although the defection is not without incident. Kusenov, whose case file at the K.G.B. was primarily N.A.T.O., is running away from the Soviets more than he is running toward western ideals, and as such, is still reluctant to divulge any Soviet secrets. One of the things he does divulge to Nordstrom and the Americans, is that the Soviets are building up a military force in Cuba of an unknown nature. Nordstrom knows that the U.S. cannot effectively work on this file because of the strained relationship between the U.S. and Cuba that has thus far culminated with the Bay of Pigs incident. As such, Nordstrom asks his old friend, French Intelligence Agent André Devereaux, whose cover is as a commercial attaché, to pursue this matter on the U.S.'s behalf, albeit without it being officially on the books as a French operation. Devereaux agrees if only because of his own intel as to Kusenov's defection, and further intel he is able to get from one of his Franco-American sources as to Cuba. It, however, places a strain on his marriage, as it will eventually take him back to Cuba to work with Juanita de Cordoba, the widow of a hero of the Castro-led revolution, and now a lead figure in the anti-Castro underground. Devereaux's wife, Nicole, surmises correctly that Juanita is her husband's mistress, an accusation he denies. Beyond being able to get the necessary information in Cuba, which places Devereaux, Juanita, and her team's lives in danger, Devereaux may have further problems if Kusenov is forthright in his information on a covert operation code named "Topaz".
A highly ranked Russian official, Boris Kusenov, his wife and daughter defect to America. Hoped to be a boon for their efforts battling the Cold War with Russia, the Americans soon find out that they have more to deal with than first thought, with Kusenov being less than cooperative, especially in regards to anything to do with a known leak in the French government, codenamed "Topaz", which has seen top secret files leaked to those in Moscow. On discovering an agreement between the Russians and Cubans, agent Nordstrom enlists the aid of his friend, and French Intelligence Agent, André Devereaux, who, at this time, is accompanying his daughter Michele on her honeymoon with journalist Francois Picard. André accepts, but his wife Nicole is worried for him. After managing to get ahold of some seriously damning papers from the visiting Cuban official Rico Parra, sneakily of course, a concerned Devereaux jets off to Cuba and catches up with his mistress Juanita de Cordoba, who is now secretly involved with a local underground movement while also being involved in another way with Parra. He finds out and kills Juanita. Ever the jet setter, Devereaux is now off home to Paris to get to the bottom of this whole leak problem. Michele wants to reconcile her parents. Nicole cheats André after his Cuban affair with the leader of the spy-ring "Topaz", Jacques Granville. Francois goes on, to find out, who is "Topaz", and he interrogates N.A.T.O. official Henri Jarre. A short time later, Michèle finds the murdered Jarré, and Francois is missing.
In 1962, the highly ranked Russian intelligence officer Boris Kusenov defects to the United States of America with his wife and his daughter under the protection of C.I.A. Agent Michael Nordstrom. In Washington, D.C., Boris discloses the Russian movement in Cuba, and Nordstrom asks the French Agent and his friend André Devereaux to get further documents from the Cuban leader Rico Parra using his anti-American corrupt secretary Luis Uribe. Then Devereaux travels to Cuba to get additional evidence of the Cuban missiles with his mistress Juanita de Cordoba. When Devereaux returns, he receives orders from the French government to return to France to explain his participation in Cuba. However, Nordstrom schedules a meeting of Devereaux with Boris, and the ex-K.G.B. official tells him about "Topaz", the codename for a group of French officials in high circles who work for the Soviet Union. Further, he tells that the French N.A.T.O. representative Henri Jarre is the second in the chain of command of the spy ring "Topaz", leaking classified information to the Soviets, and the head of spies in known only by the codename of "Columbine". Devereaux realizes that he cannot reveal the truth before finding who the traitor is.
- The story is set in 1962 and opens with images of a Soviet military parade on the Red Square. In Copenhagen, Denmark, a high-ranking Soviet intelligence officer defects to the West with his wife and daughter after a chase through the streets from the Soviet embassy to the US embassy. Upon arrival in Washington, DC, CIA agent Nordstrom (John Forsythe) debriefs him and learns that Russian missiles are to be posted in Cuba. Nordstrom enlists the aid of his friend and French agent André Devereaux (Frederick Stafford), encouraging him to accompany his daughter Michèle (Claude Jade) on her honeymoon with journalist François Picard (Michel Subor) as a premise to get him to New York. André accepts, but his wife Nicole (Dany Robin) is worried for him.
In New York City, André entrusts a familiar contact, a Hatian immigrant and former French secret agent named Philippe Dubois (Roscoe Lee Browne), who currently runs a local flower shop in Harlem, to get hold of some seriously damaging papers concerning Soviet plans in Cuba from the visiting Cuban official Rico Parra (John Vernon playing a Fidel Castro-esq character). Parra is in New York to appear at the United Nations and stays at the Cuban consulate in Harlem to show solidarity with "the masses". Dubois, taking the identity of a black journalist from Ebony, sneaks into the embassy (which is seething with visitors and surrounded by an enthusiastic mob), manages to take photos of some of the documents and then runs away, chased by Cuban revolutionaries. While cunningly dodging away, Dubois shams bumping into and overthrowing André Devereaux, who was watching events from the other side of the street, and slips the camera into his hand. A Cuban guard helps André to get up, stares at him, and lets him go. Dubois manages to escape from his Cuban persuers and returns to his job at working in his flower shop.
After examinting the photos, Devereaux confirms that the Soviets are secretly transporting and placing nuclear missiles in Cuba. Devereaux, unheeding of his wife's fear and jealousy, jets off to Cuba to find out more details. He catches up with his Cuban mistress Juanita de Cordoba (Karin Dor), widow to a former first-hour wealthy "hero of the Revolution", and herself now leader of the local underground resistance network: she acts undercover and collects information as Parra's lover. André, on arriving, finds Parra leaving Juanita's mansion. During a scene of intimacy in the mansion, Devereaux asks her to somehow take photos of the missiles as they are unloaded from Russian boats at the harbor. But Juanita's people are arrested and tortured, while Parra's man, during a big mass rally held during a lengthy speech of the "leader màximo" recognizes André's face from the incident in front of the hotel.
Parra, who has heard from the maimed and tortured female underground member that Juanita is their leader, confronts Juanita and, hugging her in his arms, shoots her to save her from being tortured to death.
In one of the film's most memorable shots, Juanita is seen from overhead, her dress spreading out on the floor like a bloodstain (although it is purple not red) on the big black-and-white pavement tiles, as she collapses.
André is arrested is searched thoroughly at the Havana airport on departure, but the Cuban authorities are unable to find the carefully hidden microfilms, which provide crucial information for the CIA about Soviet activities in Cuba. André finds them hidden behind the cover of a book that Juanita gives him prior to leaving just before she is killed by Parra.
At this point, the plot of the movie completely changes course. When André arrives back in Washington, he finds his home empty: his wife deserted him due to his Cuban love interest and returned to Paris. He is also recalled to Paris, but before he leaves, he is informed by Nordstrom about the existence of a Soviet spy organization called 'Topaz' within the French intelligence service. He is given the name of one certain member, NATO official Henri Jarré (Philippe Noiret), who leaked documents to the KGB.
On arrival back in Paris, Andre attempts to get to the bottom of the leak, while his daughter Michèle wants to reconcile her parents. He invites some of his old friends and colleagues, including Jarré, to a lunch at a fine restaurant, "Chez Pierre". While Jarré eats, André tells the others about Topaz in order to provoke some reaction. Jarré answers that all this is a piece of misinformation, since he knows that the Russian official in fact died a year ago. But he begins to panic, and visits the man who is the leader of the spy ring, Jacques Granville (Michel Piccoli). But Granville, in his night gown, is "waiting for somebody". As Jarré is leaving Granville's house, a woman arrives. It is Nicole, André's wife, and as they kiss we see a photo on a stand: Devereaux, Nicole and Granville were old friends from their days together in the French Resistance...
Devereaux sends his son-in-law François to interview and extract information out of Jarré. François calls Devereaux from Jarré's home, but the call is cut short. Devereaux and Michèle rush together to Jarré's flat, and find him dead having been thrown from his second floor window and landing on the roof of a parked car. François has disappeared.
André and Michèle return to Nicole's, and a short time later François arrives: he was clubbed, but came to and managed to escape from his captors' car. He has overheard a phone number and shows a sketch of Jarré. Nicole, who was staring at the window then turns around and tells her family, with tearful eyes, that the phone number is Granville's, so he must be the leader of the "Topaz" organization.
Devereaux goes to meet Agent Nordstrom and the Presidential entourage at Orly Airport, and to tell him about Granville. Nordstrom and company then tell the French they will brief them on the missiles in Cuba, but insist Granville not attend.
The next morning, Devereaux and his wife, now obviously reconciled in mutual forgiveness, board a Pan Am flight back to Washington. And watch, she in revulsion, he in sardonic good humor, as Granville, bidding Devereaux "Bon voyage," boards an Aeroflot flight back to Moscow. "He never misses a trick," observes Devereaux. "But at least that's the end of Topaz."
A few days later, the New York Herald-Tribune prints the news that Khruschev has agreed to dismantle the Cuban missile bases. An anonymous reader, sitting on a bench on l'Avenue des Champs-Élysées (with l'Arc de Triomphe in the background), reads the article. He then folds up the paper, sets it on the bench, and walks away.
Note: The above is one of three endings for this film that Hitchcock shot. The DVD release has all three:
1. In which Granville boards a flight to Moscow in front of Devereaux, who shrugs and says, "Well, at least that's the end of Topaz." The final scene plays out as above.
2. In which, after the French authorities dismiss Granville from the meeting, we look down the street where Granville lives. A single shot rings out. We presume Granville has committed suicide. The final scene shows the headline about Khruschev withdrawing the missiles from Cuba, against a montage of those who lost their lives to achieve that result. But this time the passerby, instead of leaving the paper for others to read, puts it into a public trash basket.
3. In which Granville and Devereaux arrange and fight a duel with pistols. Granville, of course, loses.
American TV networks, showing this film on their prime-time movie slots, typically showed the second ending. So also did various broadcast stations who acquired Topaz in syndication. But HDNet-TV, showing this film for its 2015 Alfred Hitchcock festival, showed the first ending.