Operation Saber. Ethan Cheng courted Mabel. Ethan discovered the book related to Operation Saber. Mabel was a Japanese spy. After Victor Cheng's assassination, Operation Saber was entrusted to Ethan. Joseph Qiao sacrificed. Ethan, Uncle Chang, Irene Yan decrypted music box text. Mabel set fire; Ethan killed Mabel. Irene Yan, Joseph's sister-in-law, transferred the plan. Ethan joined the resistance. Operation Saber restarted, heading to the anti-Japanese war front lines.