Carson Dyle was the antagonist of the 1963 movie Charade.
He was portrayed by Walter Matthau, who is perhaps most well known for playing Oscar Madison in the Odd Couple.
During World War II Dyle was a member of the Office of Strategic Services, which later became the Central Intelligence Agency after the war. During the war Dyle, Herman Scobie, Leopold W. Gideon, Charles Lampert, and Tex Panthollow were sent on a mission to delvier $250,000 in gold to the French resistance. The group successfully infiltrated occupied France but instead of delivering the money to the resistance Dyle and his compatriots buried the money in the countryside. The group was ambushed by the Germans with Dyle being left for dead by his compatriots. Lampert double crossed the group and made off with all the money by himself.
After the war Lampert married a young woman named Regina (Reggie) and the couple lived in Paris. While Reggie was away at a ski resort Dyle came to Paris looking for Lampert and killed him before he could escape Paris. The other members of his group, unaware that Dyle was still alive, came to Paris looking for the stolen money.
Obtaining access to the U.S. Embassay at Paris, Dyle found that CIA administrator Hamilton Bartholomew was in the habit of leaving his office unlocked while he and his secretary were at lunch. Posing as Bartholomew Dyle contacted Reggie and convinced her that he was trying to ensure her safety and find out what happened to the money so the government could retrieve it. What Dyle didn't realize was that Treasury Agent Brian Cruikshank was also stationed at the embassay and was tasked with retrieving the stolen money for the U.S. government. Working undercover Cruikshank assumed several aliases, including that of Peter Joseph, Dyle himself, Dyle's brother, and a professional thief named Adam while protecting and falling in love with Reggie.
Using information he obtained from Reggie, Dyle murdered Herman, Leopold, and Tex in turn while making it appear that Brian and Reggie were guilty of the crimes in the hopes that the French would decide they was guilty and guillotine both of them. After Reggie found that the gold was used to purchase rare stamps she was able to retrieve them after giving them to her friend's child Jean-Louis, who had sold them to a trader for 10 Francs. The trader confirmed the value of the stamps but willingly returned them. Daly convinced Reggie that Cruikshank (who was then using the alians of professional theif named Adam) was on to her and would target her next. Daly told Reggie to meet her at the Colonnade at the Palais-Royal.
Seeing that Cruikshank was following her and fearing that her life was in danger Reggie called the embassay and reached Bartholomew's secretary, who informed her that Bartholomew was away from the office. After Reggie insisted she was in mortal danger the secretary called the real Bartholomew who had no idea who Reggie was but said that the embassay should contact the local police for assistance. At the Colonnade Dyle revealed his actual identity to Reggie, and demanded she give him the stamps. Cruikshank arrived and got in a shootout with Dyle. Runing into the theater Reggie tried to hide in the stage's prompt box, but Dyle found her. Meanwhile below the stage Cruikshank located the controls for the trap door and opened the door Dyle was standing on, causing him to fall to his death just as he was going to shoot Reggie.
The following day Cruikshank revealed his actual identity to Reggie and proposed marriage to her. He also asked his secretary to compose a memo to the real Bartholomew suggesting a tightening of security measures at the embassay.