The Shanghai Cobra

Three bank employees are killed with cobra venom, and Detective Chan recalls a disturbingly similar case from ten years earlier in Shanghai. The method hints at a meticulous, unseen killer who can strike without direct contact. The case pulls Chan into a new investigation with high stakes.

In Shanghai in 1937, the criminal Jan Van Horn is badly burned during a Japanese bombing. After plastic surgery, he escapes custody and vanishes, leaving the world unsure of his current appearance. The city is left with a dangerous mystery surrounding his identity.

Inspector Davis, in charge of the present-day case, contacts Chan, rekindling their old friendship. He reveals that the bank houses the central radium depository for much of the United States, deepening the stakes. The call ties the present crime to a larger, more dangerous conspiracy.

The bank's vault is formidable, seemingly impregnable from the outside. Charlie discovers a labyrinth of underground tunnels and sewer pipes that run beneath the building, explaining how intruders and victims can be reached unseen. This revelation shifts the investigation underground.

Tommy Chan and Birmingham, often bending orders, spend a substantial time exploring the tunnels. They uncover a fourth body, confirming the killer is operating within the bank's hidden infrastructure. The discovery raises the stakes and intensifies the pursuit.

Detective Larkin, posing as the bank janitor, appears to have learned too much about the operation. His suspicious behavior foreshadows a broader conspiracy. The team realizes someone high up may be orchestrating events from the shadows.

There was no actual snake; the victims died out of reach with no direct contact. Charlie identifies a thread: the first three victims all patronized the same inexpensive restaurant. A poisoned needle concealed in a jukebox coin return becomes the killer's silent weapon.

Chan locates the jukebox control room on the bank's second floor, hidden behind a bookcase in an office that houses a full chemical laboratory. The operator who runs the booth is arrested, but she swears she has never met her boss. The scene hints at a mastermind directing the crime from elsewhere.

The booth operator is interrogated but asserts she has never seen her employer. Charlie concludes the real mastermind hides behind a veil of anonymity. The investigation pivots to identifying the chemical lab owner who orchestrates the scheme.

Chan plants a false rumor that the radium will be moved the next day, forcing the criminals to strike that very night. Security tightens as the bank braces for a heist targeting the radioactive assets. The rumor creates a critical window for law enforcement.

A cave-in locks Chan, Tommy, and Birmingham in the tunnels, cutting off escape. Chan taps the underground phone lines and sends a Morse code signal to summon help. Police flood the tunnels, sealing the criminals' fate.

Once freed from the cave-in, Chan exposes two identities: Chief Bank Guard John Adams is revealed to be the escaped Van Horn, though he is ultimately innocent. The real mastermind is Mr. Jarvis, owner of the chemical laboratory, whose poison-needle lighter murdered Detective Larkin. The case is closed with the unraveling of layers of deception.