The Saint franchise consists of European and American action-mystery thrillers, including film, radio, and television mediums. Based on the writings of Leslie Charteris, the plot centers around the titular vigilante investigator who operates outside the bounds of the law, under various disguises and aliases; commonly known by the moniker "the Saint".

The franchise has received noted success through decades of media, and has a reboot film in development.

A series of novels, short stories, and novellas authored by Anglo-Chinese writer Leslie Charteris between 1928 and 1997; centered around the character Simon Templar / The Saint. The character is a heroic charming investigator operating as a contemporary Robin Hood-like vigilante with various aliases and disguises who is characterized by his devil-may-care attitude, while evading law enforcement. Though the initial novel was released in 1928, the origins of the character are evident in early works of the author, some of which predated the first Saint novel. An early Charteris book titled Daredevil not only featured a heroic lead who shared similar traits including driving the same make of vehicle, but also featured Inspector Claud Eustace Teal, a recurring character in various Saint books.

When a series of consecutive lawless acts take place in New York, the commissioner of police hires a British investigator who fights criminal corruption through unorthodox methods named Simon Templar. Known to the law enforcement as "the Saint", Templar quickly begins dismantling criminal organizations throughout the city. When he discovers that there may be a mastermind hiding in plain sight, he begins to turn the offenders against each other, while he draws closer to resolving the corruption.

Simon Templar is hired to investigate a purported suicide of a seemingly disgraced police inspector in San Francisco, when the man's daughter calls into question the nature of his death. With her suspicions that a criminal organization is involved Templar discovers that prior to the man's untimely passing, he had also been framed for corruption which lead to his dismissal from the police force. Determined to exonerate the man of the lawful misdeeds that he did not commit, "the Saint" races against time to solve the mystery and bring justice to those who are guilty.

Simon Templar returns home to London, where he becomes involved in an investigation in a local gambler who may be guilty of being a part of a counterfeiting criminal organization. Throughout the investigation, he hires a former-thief and a socialite to assist him with the case. Templar begins to question the nature of the situation suspecting that an inspector who is also working on the investigation may be involved, "the Saint" works overtime to resolve the mystery before its too late.

Simon Templar finds himself the suspect when a shipment of mummies that were sent to his friend, an archeological professor is found with some stolen diamonds. Believed to have become a jewel smuggler, he races against time to find the perpetrator who framed him for the crime. When he begins to investigate the series of events that preceded the disappearance of the valued items, its discovered that his double Duke Bates is the mastermind. "The Saint" sets out to prove his own existence, apprehend the criminals involved, and reinstate his credibility.

Simon Templar takes a transatlantic trip to New York so that he can assist his old friend Inspector Fernack, who has been suspended due to suspected involvement in bribery. During the investigation, Templar confronts a series of gamblers who have organized fixed horse racing. As he attempts to prove his friend's innocence "the Saint" becomes familiar with a beautiful woman, who maybe have a deception of her own.