After the change of scenery in the season opener, we are back with the standard episode we’re used to seeing. There’s a case to be solved and a revelation about one of the characters: Joan Watson. As I stated in last week’s recap, the formula of the show works because of the compelling performance by the actors and this week is no exception.
The episode opens with a guy getting robbed at knifepoint. During the getaway, the robber, named Benny Charles, passes by a window when shots are fired. The shooter exits the building as the robber pleads with him, saying he doesn’t want trouble. He gets shot anyway.
Watson is leaving flowers at a grave when she’s approached by a man named Joey Castro, whose father is the one Watson is visiting. They clearly have a past as he mentions Watson was a good doctor.
Meanwhile, at the previous crime scene, Sherlock arrives as Detective Bell is investigating, and apologizes for being late. Bell tells him he’s not late because Holmes had texted him after hearing of the shooting on the police scanner. Bell texted back and told him he wasn’t needed, though Holmes goes to great lengths to prove him wrong. I love their relationship. Bell is given depth and dimension and a substantial back story when he could have easily been written as a one-dimensional antagonist to Holmes.
The victim in the apartment was Felix Soto, a math tutor who lives alone. Benny Charles, the robber outside, was found by the responding police officer and sent to the hospital, still alive, if barely. Soto’s murder is not likely robbery related as nothing is missing and a neighbor heard Soto arguing with another man a short time ago. What’s odd is the room in which Bell and Holmes are now standing, which is completely empty — no furniture, nothing on the walls. Bell speculates that maybe the shooter took something down, but there are no holes in the walls, indicating something was placed there. As Bell speculates, Holmes is essentially sniffing the walls. Holmes is impressed with Bell’s deduction skills, wondering if his methods are rubbing off on Bell. It was a question sincerely asked and was answered sarcastically saying that he had never closed a case before Holmes came along; neither had the rest of the department.
Moving on. Holmes needs a black light as what he smells on the wall is the chemical used for invisible ink and that can only be seen when exposed to ultraviolet light. A black light is found and what it reveals is math formulas (or maths as the British Holmes refers to it) scrawled all over the wall. The big question? Does the mess of formulas have anything to do with Mr. Soto’s death?
Watson and Joey catch up at a diner. Joey can’t believe that Watson went from surgeon to consulting detective. He’s dropped out of college as a result of his grief over his father’s death. Instead of becoming an engineer, he’s opening a bar, a business enterprise pursued by many who find themselves at loose ends. In fact, it’s fate that he’s run into Watson today because this is a surefire investment, indeed. It’s a way of paying Watson back for being so good to his dad.
Watson returns to the brownstone to find the math formulas from Soto’s apartment projected on the walls and a shirtless man in glasses standing in the common room. Sherlock is downstairs and the shirtless man is Harlan Temple, a professor and mathematician. Like all brilliant men on TV, he has a unique method for solving problems. In Temple’s case, he prefers not wearing clothes while working. As Holmes and Watson work through the case in the kitchen, they deduce that it’s logical that Soto was killed because of the formulas on the wall since he went to great lengths to conceal them. As Holmes is cooking eggs, Watson asks for a $5000 advance on her salary so she can, “Help out a friend.”
Before Holmes can inquire further, Temple shouts from the other room that he knows what the formula means. He proclaims Soto was a mathematical genius, though he is swiftly corrected by Holmes who states it’s the work of two men. Soto’s handwriting is matched to samples Holmes collected at the crime scene and Watson explains how the shaping of certain letters indicate his partner was male. Anyway, the two men were both geniuses as they were working on P vs NP, one of the most famous problems in math history. Knowledge of the problem escapes Holmes since he had to consult a mathematician in the first place.
The problem is one of the hardest to solve in the world According to Wikipedia (since this is an actual real life problem), P vs NP “asks whether every problem whose solution can be quickly verified by a computer can also be quickly solved by a computer.” Sounds simple, but it’s apparently messy and some believe it’s an unsolvable problem. Temple thinks the two men working on the problem were only weeks away from solving it. As to the question of whether the solved problem could be a motivation for murder, the short answer is yes. The Millennium Prizes are an award of $1 million for solving one of the seven hardest math problems in the world, including P vs. NP. Given that Soto’s neighbor heard him arguing with another man, maybe his partner thought he could complete the problem on his own without having to share the prize money. Since Soto wouldn’t be working with just anyone, the detectives should look into the P vs. NP community to find a possible suspect. Temple suggests they talk to Tanya Barrett, a college professor who knew Soto through an article she wrote profiling mathematicians who were devoted to solving the problem. Barrett’s unsure if Soto was close to anyone else she featured in her article given that he was very competitive. Barrett herself tried to solve the problem, devoting three years of her life to it before giving up.
Holmes finds a sample of writing that matches the handwriting of Soto’s mysterious partner in one of Barrett’s journals. The handwriting belongs to a guy named Nouwen, a savant living in Brooklyn. After a cheap joke about his likeness to the Unabomber (this episode was filled with cheap jokes aimed at “nerds”), Holmes calls Detective Bell with news of their possible suspect. It’s a good thing since there has been another murder with the same gun used to kill Soto. It’s a bad thing since the victim was Nouwen himself.
In the morgue, Holmes and Watson speculate on who might have known how close the mathematicians were to solving P vs. NP, despite their secrecy. Also, why did Nouwen have dog hair (determined by Homes from a photo to be the hairs of a Boston Terrier) under the arms of his coat? Were they picked up as he was dragged through an alley? Perhaps the shooter owns a dog?
Continuing the tradition of having heart-to-heart conversations around dead bodies, Watson brings up the question of the salary advance discussed earlier. It’s not a stretch for Holmes to figure out that the person who asked Watson for the $5000 is connected to the man who died under Watson’s care. Holmes, using various clues, deduces that Watson regularly visits the man’s grave. Watson for her part reacts silently with looks and gesture. I love how Lucy Liu can convey so much with just a look.
What follows is the story of what happened three years ago. Her patient was Gerald Castro. He needed surgery to remove his right adrenal gland because of tumors, a pretty straightforward procedure. Watson hit a vital artery during the surgery and he bled to death in seconds. Watson is not sure how it happened, but she killed a nice, hardworking man. The wife sued, the court case was ugly, but Joey wrote her a letter stating he didn’t blame her for his father’s death. It meant a lot to her at the time. Holmes takes in the entire story and asks if this is the first time Joey has asked for money. Apparently not, since Joey needed a car for college and to help his mother. Her answer reveals much.
A phone call from Bell effectively ends the conversation. As he was checking out Nouwen’s place for any black lights, he finds a bug. Someone was listening in on the mathematician’s conversations. The CCTV across the street from his apartment had a camera directed right at his apartment too. Using a taxi van as a ladder, Holmes discovers a signal jumper that someone used to hijack the camera. The signal can be traced back to a receiver, and possibly the murderer.
The trio head to Roe Encryption Technologies, a company that offers high level encryption services to retailers, banks, and the like. The signal was traced back to the company. The head of the firm, Linus Roe, states he did not know Nouwen until he was informed of his death. Soon, though, he reveals that he knew the man after all. He admits his company was monitoring Nouwen though he denies anyone at the company would hurt him. Roe’s company wants the problem solved, not for the Millennium Prize, but because solving that problem is worth a lot of money to his company. The solution would render all encryption software obsolete. It’s the key to building the skeleton key for getting past anything guarded by encryption. Despite Roe’s protests, it is a plausible motive for murder. Except Roe wanted Nouwen to solve the problem. He had approached Nouwen, offering funding for his work if Nouwen would help him develop cryptology to counteract programs that used P vs NP to solve various encryptions, setting the company up for massive profits. He also admits his company infiltrated Soto’s apartment, taking pictures of his work; however, their own mathematical expert claims that the pair was nowhere near solving the problem; a claim that runs counter to Temple’s assessment. Turns out, Roe’s expert was no other than Tonya Barrett.
At the police station, Barrett apologizes for not being entirely truthful with Holmes and Watson. She only consulted with Roe Encryption Technologies because she needed the money. She claimed the pair had gotten further than anyone, but were still years away from solving the problem, also counter to what Temple claimed. Barrett is also the owner of a Boston terrier, the same breed whose hairs were found on Nouwen. She also had a registered 9mm handgun, the same used to kill both Soto and Nouwen. Barrett says she was robbed, but is accused of using the burglary to cover up the fact that she still owns a handgun. The evidence against her is solid, but she claims an alibi; she was having dinner with a friend, Dean Kaneshiro, at the time the murders took place.
Bell had a hard time tracking down Kaneshiro, but the restaurant she claimed to have dined at sent security footage and lo and behold, she was telling the truth. She couldn’t be the murderer (there was still 20 minutes left in the episode, the audience could figure it out too).
Back at the brownstone, Holmes is doing sit-ups in front of his wall filled with pictures because exercise increases blood flow and helps deductive thinking. He is also shirtless, which I enjoyed because I’ve had a long-standing crush on Jonny Lee Miller. The wall has pictures of various contenders for solving P vs. NP. Not related to the case, Holmes decides that he would, against his better judgment, give Watson the advance on her salary, despite the evidence that Joey is using Watson’s guilt over his father’s death to ask for money. In a box is $22,000, a kind of buy-out Watson can give to Joey so he will leave her alone in the future, no strings attached. Instead of facing the implications of the conversation, Watson refocuses on the case, asking if Barrett had a partner who actually committed the murders while she dined at the restaurant. The hitch being that a partner using Barrett’s own weapon could easily frame her for the crime. What if that’s the point? What if Barrett is the lead suspect because someone wants her as the lead suspect?
The next day, Holmes confronts Barrett, asking if anyone else knew of Soto’s and Nouwen’s work or if she had any enemies. There is one person: her ex, Jason Harrison, who she dumped after a long relationship. He has a temper. At the police station, Bell, Watson and Holmes question the man who sent Barrett threatening emails and who knew the murder victims through his ex. The emails justify a warrant, which reveals an email from Harrison to Barrett, specifically mentioning Soto and Nouwen and an online receipt for 9mm ammunition.
The case seems at a close when Captain Gregson tells the trio that Benny Charles has miraculously woken up. If he identifies Harrison as the shooter, the case is closed. After trying to get a deal, Charles does not identify Harrison as the shooter; he identifies Barrett. So how could Barrett be in the restaurant during the times of the murders and still kill Soto and Nouwen? Doppelgänger perhaps?
It’s a conundrum Holmes and Watson contemplate at the police station when Holmes brings up the subject of the money. He suspects Watson won’t take it. Watson refocuses on the case, pointing out that a man is buying four beers at the bar for $10, which is ridiculously cheap for a upscale bar at any time except for happy hour. They figure out that the footage from the bar is accurate, but the timestamp has been changed. A confrontation later reveals that Barrett had already solved P vs. NP and with the help of her computer programming friend, Kaneshiro. She used the program to bypass encryption software and change the timestamp on the surveillance video. She and Kaneshiro, who incidentally was her dinner partner the night of the murders, were writing individual formulas to steal millions from financial institutions and Soto and Nouwen were about to ruin her scheme if they solved the problem. When confronted with all the evidence, her partner throws her under the bus.
The episode finishes with Watson meeting Joey and telling him she will make an investment, but not in the bar. She offers the $22,000 as a kind of scholarship to finish his studies. Unfortunately, like all good moochers, he only wants to keep the cash source open. Back at the brownstone, Holmes is taking a last look at P vs. NP since the NSA wants the formula and Barrett because of the security implications of the solved problem. Barrett wants a deal in exchange for her knowledge, but the federal authorities aren’t interested so the problem remains unsolved and modern encryption remains safe. Lastly, in a showing of true friendship (and why I love this pair), Holmes offers to go with Watson the next time she visits the cemetery in order to pay his respects to the man whose death led Watson to him. Watson likes the idea.