Eleanor Bennett loses her battle with cancer, leaving her children a flash drive that holds untold stories of her journey from the Caribbean to America; the stories shock her children and challenge everything they know about their family's origin.

A year after the death of his friend and partner Sherlock Holmes at the hands of Moriarty, Dr. John Watson resumes his medical career as the head of a clinic dedicated to treating rare disorders. However, he soon finds that his old life is not done with him yet.