Enola Holmes - sister of the world's most famous detective, Sherlock Holmes - always has an eye for mystery-solving. Still on the run from her brothers, Enola continues her investigative work in the busy streets of London, disguised under a new alias, and is now searching for the missing Lady Blanchefleur del Campo.

She soon finds out that Sherlock is searching for Enola herself, but not to return her home this time. He has a message from their long-lost mother, a message only Enola can decipher. Armed with clues about her mother's whereabouts, Enola walks a path of self-discovery and reconciliation. Will Enola finally be reunited with her mother? And can she solve the mystery of what has happened to Lady Blanchefleur del Campo before it's too late?