Gabriel, portrayed by Dirk Bogarde, relentlessly pursues £50 million worth of diamonds, placing the British secret service under pressure to devise a strategy to prevent their misuse. Having experienced difficulties with prior agents—who were either ineffective or no longer available—they turn to the captivating Monica Vitti, who shares the title role, and her stylish associate Garvin (Terence Stamp) for assistance in this risky operation. The story revolves around oil rights, with the stolen gems intended to support an Arab sheikhdom; consequently, deception is widespread throughout the film’s two-hour runtime as the alluring yet astute protagonist struggles to evade capture, potential torture, and disloyalty. While it isn't terrible, the movie does suffer from being overly protracted and sluggish at times. The spy aspects held promise—it evokes echoes of "Thunderball" (1965), complete with a villainous mastermind, his luxurious yacht anchored off an island surrounded by strikingly blue waters, and silent bodyguards—but Bogarde’s portrayal is marred by an irritating sense of self-importance, as if he's conveying the message that he's being generously compensated for his work. A revelation emerges near the end, suggesting a surprising connection between the spy and the sheik (Clive Revill). The film boasts a capable ensemble cast, and it maintains a generally lighthearted tone, making it watchable despite its occasional predictability.

Source on TMDB