Season: Six — Episode: 21 Director: Christine Moore — Writer: Robert Doherty — Aired: September 17, 2018 — Viewers (millions): 3.10 Summary: Holmes and Watson face their greatest challenge to date when a murder investigation threatens to destroy their partnership.
No. We're much better than that. We're two people that love each other. We always have been.
— Holmes to Watson
In the wake of Michael Rowan's killing, Watson is questioned by FBI Agent Mallick. Watson's alibi is weak as she was at her parent's house, but only her mother was present. Mallick believes Watson killed Rowan as an act of obsession after he invaded The Brownstone and attacked her. Mallick plays Watson a recording of Rowan leaving an internet voicemail for William Bazemore when he was killed in which Rowan says "Joan." Watson asks for a lawyer. Holmes and Watson consult with an attorney who believes she'll have a tough time defending Watson and indicates that Mallick wants Watson imprisoned. In private, they confirm that neither of them did kill Rowan and without the NYPD's help, Holmes says they'll have to cheat in their investigation. Holmes surprises Captain Gregson at his home and asks for help which Gregson can't give as he's being too closely watched.
I wanted him behind bars too.
At the Brownstone, Holmes has Watson review Rowan's autopsy report which he stole from the Morgue. He's blown up a picture of Rowan's corpse significantly. Watson notices that Rowan's orbital bone was fractured meaning he was concussed as he died and, that the wound Watson inflicted on him when he attacked her has been stitched up by a former Vietnam war medic. Holmes has an idea who the medic might be. At a support group meeting, Holmes confronts Denny Mulgrew. In private, Mulgrew admits to helping Rowan but didn't know he was a serial killer. Rowan told him he was stabbed trying to buy drugs. He let Rowan stay at his house overnight but he left in the morning. When he learned of the accusations against Rowan, he kept quiet, fearing imprisonment. Holmes says he'll protect him from the police if he helps him.
Note the wound you inflicted.
Holmes has Watson meet him at Mulgrew's house. He asks her to don a hairnet and surgical mask so she'll leave no DNA. He finds some traces of blood splatter and that the floor has been chlorinated. Spraying luminol on the floor, he sees woman's shoe prints that are the same size as Watson's. Later at the Brownstone, Holmes remarks that they are far ahead of the FBI's investigation and posits that Mallick may be the killer. Holmes has Everyone look into her but when Watson proposes they tell the FBI about the crime scene, Holmes says that he had Mulgrew burn his house down. He impresses upon Watson how close she is to being charged with murder, which he won't allow. Questioned by FBI agents, Detective Bell lauds Watson and treats the agents with contempt. Joined by Mallick, she claims Holmes and Watson didn't follow the rules in their investigations and threatens to expose this in the cases Bell worked on with them, which would ruin his chance to become a US Marshal.
I feel ridiculous.
Not dissuaded, Bell meets Holmes and gives him everything the NYPD has on Rowan's killing. He tells Holmes that Mallick will do anything to pin Rowan's murder on Watson. Grateful, Holmes shakes his hand. Returning to the Brownstone, Holmes finds Watson has put his bees on an internet cam and is playing make-out music. She explains this was the price Everyone demanded for looking into Mallick. Holmes points out that Watson is being humiliated as a member of Everyone is aroused by bees. Showing her the file Bell provided, he's discovered that the garbage found around Rowan's body came from Harlem, yet he was killed in Queens. Holmes believes Rowan's body was transported by a Harlem garbage truck. At the Harlem garage, they question mechanic Curtis Jenkins whose son Graham was wrongfully imprisoned after Rowan murdered his wife. Jenkins is thrilled Rowan was killed but denies any involvement and indicates he wouldn't help even if he knew who was involved.
Everyone got back to us...
Holmes threatens Jenkins but Watson restrains him. They proceed to the manager's office to look at surveillance video but discover that the footage was taken and the originals erased by Captain Gregson.
The episode title is taken from a famous Conan Doyle Sherlock Holmes quote, "when you have eliminated the impossible, whatever remains, however improbable, must be the truth" which first appeared in The Sign of the Four. Holmes also quotes it in "The Leviathan".