When a helicopter crashes through the skylight of the Asian Art Museum, an audacious heist turns into a tragedy. The only witness to the crash is 11-year-old Grace, who watches in horror as her uncle is killed and a priceless statue stolen by two men…and a ghost? At least that's how the eerie, smoke-like figure with parchment skin and floating hair appears to Grace. Scared almost to death, she flees into the night and seeks refuge in the back alleys of San Francisco's Chinatown. Grace is found by Sally Mei, the self-appointed guardian of Chinatown. While Sally trains Grace in basic survival skills, her erstwhile partner Cape Weathers, private detective and public nuisance, searches for the mysterious crew behind the robbery before they strike the museum a second time.

At the height of tourist season, an armored car drives off a crowded pier and sinks to the bottom of San Francisco Bay. By the time divers find the wreck, the cash is gone and the driver has vanished. The police are convinced it's an inside job, but local merchant Vera Young, whose boyfriend drove the armored car, claims it was much more than a simple heist. Vera swears the missing driver is innocent and wants him found before the police can throw him in jail. Private investigator Cape Weathers reluctantly takes the case but warns Vera that her boyfriend is likely guilty --- or dead. What starts as a manhunt uncovers a criminal conspiracy of money laundering, illegal drug testing, and a network of corporations willing to do anything to protect their stock price.