The cartel recruiter slipped onto campus disguised as a janitor and then zeroed in on his target: a sophomore chemistry student.

The recruiter explained that the cartel was staffing up for a project, and that he’d heard good things about the young man.

“‘You’re good at what you do,’” the student recalled the recruiter saying. “‘You decide if you’re interested.’”

In their quest to build fentanyl empires, Mexican criminal groups are turning to an unusual talent pool: not hit men or corrupt police officers, but chemistry students studying at Mexican universities.

People who make fentanyl in cartel labs, who are called cooks, told The New York Times that they needed workers with advanced knowledge of chemistry to help make the drug stronger and “get more people hooked,” as one cook put it.

The cartels also have a more ambitious goal: to synthesize the chemical compounds, known as precursors, that are essential to making fentanyl, freeing them from having to import those raw materials from China.