Elementary - Evidence of Things Not Seen

While mulling over his father's (John Noble) offer to step-in and fix their broken relationship with the NYPD, Holmes (Jonny Lee Miller) and Watson (Lucy Liu) take on a consultant job for the FBI investigating a triple homicide in a top secret research lab. Finding the rules of the new partnership constraining, Holmes begins give serious thought to his father's offer despite knowing that there will no doubt be some cost to be paid down the line.

It's obvious fairly early on that the FBI's way of doing things, such as limiting Holmes and Watson's contact to vital evidence and leads, isn't going to be a recipe for success for long. Despite these obstacles Holmes does manage to find motive for the killings for scientists involved in a failed brainwashing experiment and identify the killer. Despite agreeing with Holmes' instinct to want to return to his old partnership with the NYPD, Watson is just as leery of the elder Holmes' true motivations, even going so far to square off against the man no doubt foreshadowing a larger conflict somewhere later down the line.