This is one of the few times that the show has explicitly referred to the original Arthur Conan Doyle canon (the episode’s title is a play on the story, “The Hound of the Baskervilles.”) However, besides the title and a reference to a cancer-finding device referred to as, “The Hound,” this episode has little in common with the original story.
The case starts out with a cancer researcher named Barry Granger is seen arriving at his office to use the communal shower, only to be killed when someone leaks helium into the room. The resulting high pitched voice just before he dies is kind of hilarious, even though I felt bad for laughing. He’s found by the police, but it’s been set up like he committed suicide. Holmes, of course, deduces that it was murder and therein begins the circular route in finding out the real killer. (Hint: it’s one of the few times the killer is introduced as a suspect early on.)
The subplot of this episode involves Detective Bell’s full re-entry back into the NYPD. He’s now been cleared for regular duty and he’s been assigned to keep an eye on a witness who is due to testify against a violent drug dealer. The problem is is that she’s disappeared. He asks Joan to help him find her and she mentions the gathering to celebrate his reinstatement at a local bar. It’s implied that she and Holmes will be attending, but Holmes spends much of the episode giving various excuses about why he can’t attend: he’s a recovering addict, he’s an outsider, he’s responsible for Bell getting hurt. It sounds like he’s having FEELINGS and wants to avoid those as much as possible. He blames Watson for making him “softer.”
Holmes: Misanthropy was so easy. Elegant. I miss it sometimes.
Watson is able to locate the young witness; she’s hiding at the home of a local teacher and legend, Manny Rose. His example is cited by Bell as one of the reasons he didn’t get involved in gang life and became a cop. The girl is scared to testify because she’s not only got herself to worry about — she’s also pregnant and wants to protect her child and her partner. Bell decides to pay a visit to Rose’s apartment and after reminiscing about the neighborhood, he tells Rose that the girl does not have to testify. The DA will have to convict the drug dealer without her, and even if he gets away this time, they’ll get him eventually. This is apparently not good enough for Rose, whose reputation is built upon taking justice into his own hands. This ends tragically when he confronts the drug dealer and manages to kill him, but at the cost of his own life. On the eve of Bell’s triumphant return, he’s faced with a tragedy that he may have had a hand in causing.
As far as the case goes, we are exposed to the high stakes world of medical research. Granger was the target of a research debunker that went by the alias Adam Peer. It seems the killer wanted to make it look like Granger was so distraught over a perceived disgrace that he killed himself. Holmes quickly disproves that theory. He discovers the woman with whom Granger was seen arguing on a surveillance video. On the surface, she’s a travel agent, but after Holmes deduces her agency is a front, she reveals herself as a Mossad agent. She also had nothing to do with the murder, so who else do we have? As a sidenote: it was nice to see Shiri Appleby back on my TV screen as the Mossad agent, Dalit. Given how brief her appearance was, I wonder if she’s someone we will see again.
What about Adam Peer, the anonymous whistleblower who has been after the research team? Nope. Turns out it was Granger all along (with the help of a partner). Since Granger’s death was a murder and not a suicide, he didn’t off himself. Someone used the pseudonym to discredit the Hound.
Well there is Hank Prince, the devastated colleague and the money behind the research who appeared to have been framed by the murderer and who was dismissed in the beginning. Because he bungled around some more in an attempt to deny his wife money in a divorce settlement and decided to kill her instead, he blew his own cover-up of Granger’s murder. He was out to discredit the study to prevent her for getting more money. When it was discovered that Adam Peer was Granger himself, the study was back on track and due to make billions. Billions that his wife would have access to.
In the end, we find Bell standing outside the bar where his celebration is taking place. After the tragedy with Rose, his heart is not into the occasion. Holmes finds him outside the bar and confesses that their job can carry high costs. It’s almost natural that he feels conflicted. In a gesture that speaks to the repairing of their relationship, Holmes asks if Bell wants to get coffee and Bell accepts. The last shot is reminiscent of Rick and Captain Renault walking off into the fog at the end of Casablanca.