The NYPD and FBI have arrested and charged a former high school teacher and his twin brother with terrorism, but not until a bizarre series of twists uncovered a serious plot. In a press conference last night, New York City police commissioner James O’Neill outlined the broad parameters of the case against Christian and Tyler Toro, but this case gets weird very quickly, and it’s unclear exactly what the motives here might be:

A former New York City high school teacher and his twin brother were charged Thursday with attempting to make explosives, in part by paying students to extract gunpowder from fireworks, officials said.

Christian and Tyler Toro, both 28 years old, had been gathering material to make a bomb since at least October, according to a criminal complaint filed in federal court in Manhattan. The U.S. Attorney’s Office, FBI and the New York police announced the charges Thursday evening.

New York Mayor Bill de Blasio said there is no evidence to suggest an ongoing threat to the city or its schools now that the two have been arrested, but he said agents are still investigating.

“We get daily reminders of the threats arrayed against us, but what we’re seeing here in this case already is, some good people stepped forward with information,” de Blasio said.

O’Neill’s statement really doesn’t do justice to the investigation, nor the stupidity of the plotters. The story has to be read in full to be believed, and it starts with a prank bomb scare suggested by the plotter himself — a high-school teacher in Harlem.

In December, a 15-year-old female student in Christian Toro’s class told him she was bored, and according to the student, Toto encouraged her to call in a bomb threat to liven things up.  When police figured out who’d called in the prank scare, she pointed the finger back at Toto — who then quit his job at the school. When Toro turned in his laptop computer, the school’s IT technician discovered that bombs may have been on Toro’s mind in other ways too, as the Daily Beast Michael Daly reports:

Shortly after the student was arrested for making the threat, the teacher abruptly resigned. He had been issued a laptop, and his twin brother, Tyler Toro, delivered it back to the school two days later.

The See Something came when a school technician came upon a downloaded book in the computer that detailed how to make explosives.

NYPD investigators decided to drop by and have a chat with Christian, who said he’d downloaded the book by accident and had only looked at the table of contents. However, the same female student that had pointed the finger at Toro for the bomb scare gave a few more details about their relationship, and it wasn’t just teacher-student. Police arrested the former teacher for statutory rape, and began interviewing other students at the school about Toro’s activities.

And that’s when they uncovered something even stranger:

Investigators were at the Upper Manhattan school on Feb. 14, Valentine’s Day—the day of the school shooting in Florida—interviewing students in connection with the statutory rape case. A friend of the accuser told the investigators that she had also been at the teacher’s apartment. She added that the teacher had paid her and her friend to empty the black powder from fireworks.

The investigators returned to the first girl, who allegedly said she ”forgot” to tell them about emptying fireworks. The next step was for the investigators to secure a search warrant.

So police got a search warrant for the apartment shared by the twin Toros — and hit paydirt:

They discovered a box on the floor of the bedroom closet containing a glass jar of black powder, 20 pounds of iron oxide, five pounds of aluminum powder, five pounds of potassium nitrate, and two pounds of confectioners sugar. A small container held iron oxide and aluminum powder that had been mixed into thermite, which the complaint describes as “an explosive material that can create heat and high temperatures.”

They also found Tyler Toro’s diary, which had all sorts of interesting comments, including this epigram: “UNDER THE FULL MOON THE SMALL ONES WILL KNOW TERROR.” Yeah, nothing creepy at all about that.

So let’s recap. The teacher had decided to build a bomb for “terror,” but rather than keep things quiet, he had teenage students emptying out fireworks for the powder in large quantities. He then started having sex with one of them, and then encouraged her to call in a fake bomb threat to relieve her boredom. If all this is true, the only thing Toro didn’t do is to install a large sign on his apartment building that said “TORO TWINS TERROR, INC.”

If stupidity was a federal crime, Christian Toro would be a death-penalty case. And yet, it apparently took all of this sequence of events for someone to finally say something about the Toros and their black-powder reclamation project. Next time, let’s hope “see something, say something” gets taken more seriously earlier in the cycle. Thankfully, an alert IT technician at the school managed to get it right.