With no warning, a guy in a black ski mask levels a gun at a man. Well, I guess there could have been some warning before the episode started. I mean that we, the audience, get no warning. Because it's the way the episode starts. As he pulls the trigger, we cut to the Brownstone, where Holmes has a fever of 101 degrees. He gets a text from Gregson about a man left in an abandoned building. And boredom is worse than a fever, so it's time to go. We're jumping around a lot so far, aren't we?
It's raining at the abandoned building, so everyone's concerned about Holmes's sickness. They're less concerned about the dead guy, because he's already dead. His eyes were shot out. Bell says it's the gun was very close to the skin when it was fired. Holmes notes there are no shell casings or skull fragments, so the body was moved here. But Bell knows that, so it doesn't count as an astonishing deduction. Watson is worried about Holmes dying of exposure because this abandoned building is missing big chunks of wall and ceiling. Holmes eyeballs the situation and examines the victim's wrists. He reports that the victim was on his feet all day (because of his comfortable shoes) but had a job where he couldn't just wear athletic shoes. And the marks on his fingers from dry erase marker mean that he was a professor. And he's been to China. His tie reveals that he's from Garrison University. And the time he spent explaining all this has allowed him to muck with his iPhone to provide a specific identity: Professor Trent Annunzio.
Now they've gone to talk to Trent's widow June. She met him five years ago in Beijing and moved here two years ago. Watson gets a call from someone named "Liam" at Riker's Island, so she steps out for a second. As June talks, Holmes noses through her CDs. Then he points out that Trent was murdered in a personal way, like someone had a grudge. She says she saw Trent the previous morning, and he had to stay late for a meeting.
Outside, Holmes plans on going to Garrison to talk to the coworkers. Watson, however, is going to Rikers to talk to Liam, who she says is an old client.
Holmes and Bell are getting a brief tour from Trent's Teaching Assistant, a Mr. O'Brien. Contrary to what June said, O'Brien says Trent did not have to work late for a meeting. They're let into his office, but Holmes is more interested in the office across the hallway. Bell thinks the office is pretty cramped for a department head, who could have picked any office. Holmes decides he was going to an underground Chinese gambling parlor. Bell can't help but ask why, and the answer is that there are a lot of thirteens in his life. He didn't want the office across the room because its number was 14, which is unlucky. And his underwear was red boxers, which is considered lucky. And his clothes reeked of cigarette smoke, but his teeth were white, suggesting that he was not a smoker. Bell is reluctantly impressed, and I like how he's filling the traditional "Watson" role of someone who Holmes can show off to. Bell finds Mahjong tiles in Trent's desk, and they're different shapes. He says they're calling cards to different club and dares Holmes to ask how he knew that. Holmes won't do it, but Bell tells him anyway: poker clubs use custom chips, so Mahjong clubs presumably use the tiles. Holmes won't admit it, but he appears to be slightly impressed.