Please answer the following question: Generate a question about the following movie plot: Set in Colonial Vietnam circa 1920s, THE REBEL references long-festering anti-French sentiments among Vietnamese, triggering the formations of guerilla forces to rise up against the foreign colonizers. In response, the French employ elite units of Vietnamese agents to track down and destroy these rebels.THE REBEL follows the plight of an undercover agent Cuong (Johnny Tri Nguyen), a man who grows increasingly ambivalent about his identity as a treacherous mercenary because of his mounting conscience, after meeting and becoming enthralled by Thuy (Ngo Thanh Van), the daughter of an infamous rebel leader. Plagued with patriotic obligations, Cuong is unsure of where his loyalty lies when he is confronted with the dictatorial reality of French rule and his own humanity reflected in Thuys eyes.
A:
Who is the undercover agent?