There’s a new detective at 221 Baker Street. Set against the background of 1930s England, Jewel of the Thames introduces Portia Adams, a budding detective with an interesting —and somewhat mysterious —heritage. Nineteen-year-old Portia Adams has always been inquisitive. There’s nothing she likes better than working her way through a mystery. When her mother dies, Portia is left puzzling over why she was she left in the guardianship of the extravagant Mrs. Jones? Portia is promptly whisked from Toronto to London by her guardian, where she discovers that she has inherited 221 Baker Street — the former offices of Sherlock Holmes and Dr. Watson. Portia settles into her new home and gets to know her downstairs tenants, including the handsome and charming Brian Dawes. She also finds herself entangled in three cases: the first one involving stolen jewelry, the second one a sick judge and the final case revolving around a kidnapped child. But the greatest mystery of all is her own. How did she come to inherit this townhouse? And why did her mother keep her heritage from her? Portia has a feeling Mrs. Jones knows more than she is letting on. In fact, she thinks her new guardian may be the biggest clue of all.