Gary Merkling, who works in a paper mill near Green Bay, Wis., flew to New York for only one day — last Tuesday — and early that morning stood in line among the throngs of reporters. Mr. Merkling appears to have a fascination with the international cocaine trade. Last year, he said, he went to Colombia to visit the estate of Pablo Escobar, the drug lord who died in a shootout with Colombian authorities in 1993.

But Mr. Merkling believes El Chapo is on another level: “I’ve been fascinated with him with for years,” he said. (People have been fascinated with El Chapo from the moment he became a well-known kingpin.)

There was another reason for the trip: He had just turned 35.

“It’s kind of like a birthday present to myself,” Mr. Merkling said.

A cartel connoisseur could not have asked for a better gift.

From the moment it began in November, the trial has offered up a cornucopia of drug-world lore — with weird, wild and seemingly unimaginable details. On a single day last week, the jurors heard about a catering company that sneaked cocaine onto airplanes, fraud involving the indigenous people of the Amazonian jungle and a jailhouse murder plot that revolved around a cyanide-laced arepa.

There has, at times, been news: On Wednesday, a witness testified that executives from Pemex, Mexico’s national oil company, once discussed a deal with Mr. Guzmán to ship cocaine in the firm’s tanker vessels.

There has also been gore: On Thursday, jurors heard the tale of a trafficker who was shot in the heart while parked at a gas station. He died with his daughter sitting beside him.

That sort of thing apparently appealed to Max Acker, a former Marine enrolled in the sports management master’s program at Columbia University. Several years ago, he said, he wrote a letter to Richard Ramírez, the serial killer known as the Night Stalker. On Wednesday, he showed up to see El Chapo with a friend who makes movies.