The writer and physician Tess Gerritsen was born Tess Tom on June 12, 1953, to Ernest Tom, a second-generation Chinese American restaurateur in San Diego, California, and his China-born wife, Ruby Tom. A 1975 graduate of Stanford University, where she majored in anthropology, Tess Tom attended medical school at the University of California Medical Center in San Francisco. She married fellow physician Jacob Gerritsen, a native of Hawaii, in 1977, and received her medical degree in 1979. Interested in writing since childhood but encouraged by her parents to choose a more lucrative profession, Tess Gerritsen began writing romantic suspense novels while on maternity leave from the practice of internal medicine in Hawaii.
In 1990, the Gerritsens and their two young sons moved to the American mainland, eventually settling in Camden, Maine, where Jacob established a private medical practice while Tess, basically retired from medicine, pursued her career as a writer, also enjoying such hobbies as gardening and the Celtic fiddle. By 2003, Jacob Gerrritsen had retired from active practice, enjoying his own hobby of sailing while serving as president of the Maine Medical Association. Tess Gerritsen, meanwhile, had teamed up with Michael Palmer to offer annual workshops for would-be novelists in the medical profession. In 2006, Gerritsen won the Nero Wolfe Award for Vanish (2005), which was also nominated for an Edgar Award.