In 1920s China, amidst the turmoil of foreign occupation and warlord conflicts, Chen Zhen returns to Shanghai after supposedly dying seven years earlier. Disguising his identity, he becomes a nightclub owner by day while donning a mask at night to fight injustice. Chen Zhen witnesses the rise of an anti-Japanese resistance movement and decides to infiltrate the crime-ridden city’s underworld, gathering intelligence and allies to defend his country from the oppressive forces. Alongside his undercover operations, he becomes romantically involved with Kiki, a nightclub singer with ties to both the resistance and the Japanese authorities, which complicates his mission and tests his resolve.

As tensions mount, Chen Zhen uncovers a massive conspiracy that threatens to plunge the entire city into chaos. His dual life grows increasingly perilous as he battles corrupt officials, spies, and ruthless assassins who are determined to maintain their iron grip on Shanghai. Balancing his loyalty to his country with the need to protect his friends and loved ones, Chen Zhen faces dangerous encounters and moral dilemmas. Although his journey is fraught with danger, he is driven by a profound sense of justice, preparing to confront the enemies of his homeland and reclaim his identity, risking everything for the sake of freedom.