In the 1967 film "Casino Royale," Vesper Lynd is a fictional character and a love interest of James Bond, played by David Niven. She is portrayed as a British Treasury agent who is tasked with keeping an eye on Bond's gambling activities in a high-stakes baccarat game against the villainous Le Chiffre.

Throughout the film, Vesper is portrayed as an intelligent and independent woman who is not afraid to stand up to Bond and challenge him. Despite her initial resistance to Bond's advances, the two eventually fall in love and begin a passionate affair.

However, as the plot unfolds, it is revealed that Vesper is not who she appears to be. She is actually a double agent working for the villainous organization SMERSH, and she has been manipulating Bond in order to carry out her mission.

Vesper's character is a departure from the typical Bond girl archetype, as she is a more complex and layered character with her own motivations and desires. Her betrayal of Bond adds a tragic element to the film and has become one of the most iconic plot twists in the James Bond franchise.

Overall, Vesper is a memorable and important character in "Casino Royale," and her relationship with Bond serves as a driving force for much of the film's plot.