Born in Detroit, Michigan, Shannon moved with his family to San Pedro, the gritty harbor district of Los Angeles, California, when he was five.

After completing his film degree, Shannon wrote one episode of I Spy, a popular television series, then made the decision to leave Hollywood for the Peace Corps.

When he returned to the United States following his two-year teaching stint in a remote town at the foot of Lake Malawi, he soon became active in the movement against the Vietnam War.

The hero of Shannon's highly praised mystery series is Jack Liffey, introduced in the first book, The Concrete River (1996), as a laid-off aerospace worker.

Depressed by his situation and self-medicating, the introspective, sensitive and quirkily humored Liffey pays for his downward spiral when his wife leaves him, taking with her Maeve, the daughter he adores.

What pulls Jack Liffey back together is a startling discovery: called upon for a favor, he finds he possesses a talent for locating missing children.

"[1] It is a statement that offers clear echoes of Raymond Chandler's famed description of the private eye: "Down these mean streets a man must go who is not himself mean, who is neither tarnished nor afraid.

About City of Strangers, the Los Angeles Times pronounced: "Shannon dishes out L.A. local color dipped deep in moral sauce.

"[6] Reviewing The Dark Streets, Publishers Weekly commented: "Shannon once again skillfully dissects the sociocultural landscape of Los Angeles.