Sherlock Holmes (Jonny Lee Miller) is called into to consult on a case of home invasion and murder that he believes is linked to one of Captain Gregson’s (Aidan Quinn) old cases. While Holmes wants to talk with the man (Keith Szarabajka) Gregson put in jail 13 years ago, Gregson is reluctant and would rather pursue other avenues of the investigation including the latest victims’ contractor (Brian Tarantina) who was keeping a woman (Evgeniya Radilova) chained in his basement and recently threatened the couple after they complained about his work.
Dismissing the new suspect, Holmes goes with Gregson to talk with the man convicted of the crimes. After talking with the killer, who still proclaims his innocence, Holmes makes a discovery that the physical evidence linking him to the third crime scene was planted by a member of the department, Gregson’s former partner (Callie Thorne). Unable to get a straight answer from Gregson, Holmes shifts his attention to a suspect (Stivi Paskoski) from the original murders who has spent the last dozen years in prison and was released just weeks before the killings started up again.
However, after finding the man with the murder weapon in his possession Holmes is convinced that Gregson’s original arrest was indeed the right one, planted evidence and all, as from behind bars the killer has orchestrated the perfect method to overturn his conviction and frame another man for his crimes. To prove his theory, and put Gregson’s fears about his partners actions all those years ago, Holmes needs only to find the man’s partner (Juan Castano) for the new murders. The last few twists work well as Gregson’s guilt is abated, and Holmes discovers the truth of the new murders wasn’t anything more than a family thing.
Unable to get any answers about his past from Holmes, Watson (Lucy Liu) takes a trip to his rehab clinic to talk with the man’s doctor (Stephen Kunken) and nurses only to come up empty as Holmes never shared anything personal in therapy. However, she does run into a gardener (Stephen Henderson) with a bee keeping hobby who seems far more promising. Her snooping doesn’t give her new insight into Holmes mystery woman, but it does uncover a single fact that Holmes was close to Irene Adler and that the detective did not take her death well (which may, or may not, have led to his downward spiral).