Season: Six — Episode: 2 Director: Guy Ferland — Writer: Robert Hewitt Wolfe — Aired: May 7, 2018 — Viewers (millions): 4.59 Summary: Watson and her half sister, Lin, have conflicting reactions when their estranged biological father dies. Also, Holmes and Watson find themselves on the hunt for a stolen plutonium shipment they fear will be used to make a dirty bomb after a Department of Energy inspector is killed with a lightning gun.
Killer's freeze ray was probably in the shop, so he used his lightning gun instead.
— Captain Gregson
At the funeral of her biological father, Watson meets her sister Lin Wen who asks to have lunch with her that week. Arguing with his wife on the phone, Rohan Giri walks down a Manhattan street until struck in the chest by a bolt of lightning. Later, Holmes stops the ESU workers sent to transport Rohan's body. He tells them Rohan was murdered as the tall buildings would have acted as a lightning rod and prevented any strikes. At the Morgue, Holmes and Watson examine Rohan's body with Captain Gregson and learn Rohan was an inspector for the Dept. of Energy. Detective Bell has called Rohan's wife, Chloe, to the 11th Precinct for questioning. She is a suspect as she's a physicist and had several disputes with Rohan in public. Holmes and Bell learn she was having an affair and was with her lover when Rohan died. She doesn't have detailed knowledge of the laser-induced plasma channel (LIPC) which may have killed Rohan, but provides them with a lab that is making one.
This man was not killed by God.
Watson meets Lin for lunch but Lin can't stay. Lin received their father's possessions and the only item of value is a sealed envelope that he wrote to Watson. With some regret that nothing was left for her, Lin says that Watson was important to him. At the LIPC lab, Holmes and Bell are shown the LIPC by an engineer, Mr. Kwon. Loaded into a truck for testing, Kwon indicates that Rohan was inspecting a mini nuclear reactor that had been built to power the LIPC. Kwan insists his company had no motive to kill Rohan as even if they failed his inspection, it would be progress for them. Holmes notes that the truck was driven the night before and Kwon finds the LPIC logs have been wiped. The truck's seat setting indicates it was driven by a tall man which Kwon narrows to one of their financiers, Dave Ambelin.
A sickly looking Ambelin is questioned in "the box" at the precinct where he denies being exposed to radioactive materials. Learning he'd recently been to Japan and with traffic camera pictures of him driving the LPIC truck, Ambelin admits to accidentally killing Rohan. He bought plutonium in Japan that was being smuggling into the US but it was stolen. He hoped to hospitalize Rohan to buy time to find the plutonium before his inspection. Later, Gregson introduces them to Agent Don Kohler of the National Nuclear Security Administration (NNSA) who will be leading the search for the plutonium while the NYPD looks for the thief. Feeling symptoms of his concussion, Holmes and Watson leave for The Brownstone where Watson examines traffic footage from near the lab. Asking about Watson's lunch with Lin, Watson mentions the letter from her father which she lies that she threw away without reading.
The pain is quite remarkable.
Watson spots a suspicious delivery van in the footage and later with Bell and Kohler, the van is found. Reported stolen and then recovered, radiation is detected in the rear of the van. From the mileage logs and gravel Holmes finds in the tires, it's determined the van dropped off the plutonium in Bedminster, New Jersey. The home of a felon, Hayden Wischer, who was imprisoned for bomb-making is discovered in Bedminster, complete with a bunker. Kohler's men discover Wischer shot dead inside the bunker and evidence that he made a bomb with the plutonium, which is missing. Wischer was part of a white-power gang, PAIN, while in prison. Believing that PAIN intends to use the bomb, their leader Colm Frick, who is on parole but has disappeared, becomes the next search target.
Not in the woods. Under them.
At the Brownstone, while reviewing Frick's file, Holmes notes that Frick is a passionate tabletop wargamer even in prison where the materials for it are contraband. While suggesting they review web sites for gamers, Holmes produces the letter Watson's father wrote for her. He's deduces that her father wrote the letter when he was lucid and it is important. He encourages her to open it as the final clue in a lifetime mystery but Watson decides to wait. Having discovered Frick at a wargamer tournament, he's brought to the precinct. Frick denies that PAIN is behind the bomb and that the movement is only interested in making money, which Wischer did for them. He mentions that a meeting between Winscher and some Europeans who wanted a conventional bomb was setup but the Europeans never showed.
I mean, it could be more craziness.
While discussing Frick's interrogation, Bell, Holmes and Watson are called to the bullpen by Gregson. Kohler reports that an unidentified woman has called in a credible tip that a mosque will be bombed and a taxi is being used to transport the bomb. With police teams deployed at the city's mosques, Gregson's team watch for suspicious vans using traffic camera monitors at the precinct. Bell finds a cab that is passing up fares and circling a mosque. Holmes asks to see the footage of the area the van is circling from the last hour. Police evacuate the area around the mosque. As Gregson prepares to leave, Holmes tells him that the bomb is conventional and there's no terrorist attack being planned, rather, it's a heist. At a diamond repository next to the mosque, four Dutchmen in NYPD uniforms rob a diamond company. As the Dutchmen try to leave the building, they are blocked by Gregson and an ESU team.
Tell ESU to get down to that mosque.
Threatening to detonate the bomb and poison the city, Gregson says they know the bomb isn't dirty but if detonated, they'll shoot the Dutchmen. Realizing they are beaten, the thieves surrender. At a debriefing in Gregson's office, Kohler reports that the bomb was conventional, as Holmes deduced. Holmes, Watson and Bell explain that several clues indicated the heist including the thieves entering an area that was supposed to be the blast site and a group of three thieves in NYPD uniforms when officers work in pairs. However, the stolen plutonium was required in order to lend credence to the dirty bomb threat. With Ambelin's co-operation, they've found that the port the plutonium went through had an alarm triggered that Kohler cleared and, that his new girlfriend is related to one of the thieves. His girlfriend admitted to hooking Kohler up with the thieves, she's the one who called in the threat and, Kohler is arrested.
You intentionally let the plutonium through.
Later at the Brownstone, Watson finding Holmes combating his post-concussion syndrome by working on a child's puzzle. Noticing that she's getting oranges, he deduces that she's going to visit her father's grave and assumes that she's read his letter. At the grave site, Watson meets Lin and tells her about the letter. (♫ Hollow Coves - These Memories ♫) Knowing that his health was failing, he wanted Watson to know about Lin, who he described as amazing, beautiful and who he loved very much. Lin sees that despite his condition, he was trying to make sure that Lin and Watson met. Happy that her father remembered her, Lin hugs Watson.
He wanted us to be sisters.
Hollow Coves - These Memories plays at the episode end as Watson meets Lin at their biological father's grave and tells her about the letter he wrote her.
Watson first mentions her biological father, who is schizophrenic and homeless, to Holmes as she helps Morris Gilroy who is also schizophrenic and homeless. ("Corpse de Ballet")
"It might confirm your theories about your father, it might force you to reevaluate. But it is evidence, nonetheless, and a good detective must never ignore the evidence."