Watson and the team work alongside Laila to help a patient named Maxine, who is 30 years old but looks 10 years old. Meanwhile, Watson convinces Laila that he is serious about their relationship and Ingrid is struggling to ingratiate herself back at work as a hot newcomer joins her therapy group.
A year after the passing 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.