Dr. John Watson resumes his medical career as the head of a clinic dedicated to treating rare disorders six months after the death of his friend and partner, Sherlock Holmes, at the hands of Moriarty.

Watson and the fellows investigate the perplexing case of a family man with a bullet lodged in his head who insists he is a Scottish soldier and seems to be hiding something nefarious; Watson looks for clues to whom his estranged wife Mary is dating.

Watson and the fellows treat a comic who collapsed at an open mic night; the team becomes concerned when Watson collapses and suffers another traumatic brain injury.

When Sasha discovers a link between her current patient and a cadaver she dissected during medical school, the team traces the case to Amish country.

Watson takes a major ethical risk when he decides to treat a sickle cell patient with an unorthodox surgery; Ingrid struggles to get her sister admitted to her spinal project.

Stephens musters the courage to ask Watson to help him when his camgirl suddenly collapses during a video call; the team must act quickly to locate her before it's too late; Watson grapples with guilt over Sherlock's death.