At the start of the autumn semester of 1974, John Wheeler, an esteemed physics professor at Princeton University, was enormously excited about his new recruit. It was a productive time in Wheeler’s career, when his reputation as a leading black hole expert was spreading far and wide.

Wheeler was known not only as a top notch theorist — the co-developer with Niels Bohr of a key model of nuclear fission — but also as someone with an eagle eye for young talent. Among his stellar picks was Richard Feynman, who would go on to win the Nobel Prize, and Kip Thorne, who would become one of the co-founders of the successful LIGO gravitational waves detection project.

When Wheeler learned about Dragoljub Cetkovic, a precocious 19-year-old from Montenegro (then part of Yugoslavia), who had just received a physics degree from the University of Belgrade, he was quick to inform his colleagues about the young man’s potential. Cetkovic wanted to study quantum field theory. Given Wheeler’s clout, the Princeton department enthusiastically offered Cetkovic a coveted place in its PhD program, and a TA (teaching assistantship) position for support.

“Brilliant. That was the essence of it,” recalled Wheeler in a later interview.

Unfortunately, soon after Cetkovic was supposed to begin his graduate studies at Princeton, the department realized it had made a serious mistake. The recruit was a no-show for months, skipping all of his fall semester classes. Graduate school is so rigorous that any delay can be fatal to a students’ career. Yet Cetkovic seemed indifferent to the demands. When he finally arrived on campus, he objected to taking the required comprehensive exams, and refused to teach the undergraduate courses for which he was being paid. By 1976, the department had given up and Cetkovic was asked politely to leave.

After Cetkovic was dismissed from the program, he became unhinged. He began to harass Barry Simon, the department’s director of graduate studies. Word soon spread that he was making threats against Simon’s life. The police were notified, but couldn’t find any evidence that was the case. Cetkovic also told people that he planned to commit suicide. Instead of returning to Montenegro, he remained in the Princeton region, returning to the department on occasion to beef about the supposed injustice, until he was prohibited from campus.

Wheeler, in the meanwhile, left Princeton for a decade-long stay at the University of Texas, Austin, where he worked on quantum measurement theory and other topics. Upon retiring, he returned to the Princeton area to live in a senior citizens community and enjoy an emeritus position at the university.

Much to Wheeler’s horror, in 1987 his ill-fated recruit was still in the region (long having lost his student visa) and in serious trouble with the law. Posing as a reporter, Cetkovic had called a Superfresh supermarket and told the night manager that the cheese in the store was tainted with cyanide. As proof, he pointed the manager to a tea bag left on a certain shelf. Tests were done of the tea bag and indeed it was laced with poison. The cheese, on the other hand, tested negative. In fact Cetkovic had soaked just the tea bag and left in the store; he didn’t even touch the cheese. The FBI was brought in and traced the phone call to Cetkovic’s apartment. He confessed, was arrested, and decided to plea insanity. He also claimed that he has been attempting an experiment with lethal doses to practice for his own planned suicide.

Enter Judge Maryanne Trump Barry, the sister of the future President, for whom the case was in her US District Court jurisdiction. In sentencing Cetkovic, she weighed the distress in his life along with the nature of his crime. She noted that his father was seriously ill, that he was desperate and suicidal, and finally that no one was actually harmed.

‘I was moved by the depths of despair to which he had sunk, the desperation which one human being could experience,’ Judge Barry said. ‘I do not believe that the defendant intended to hurt or kill anyone.’

Judge Barry sentenced Cetkovic to five years in a federal prison in Butner, North Carolina, where he could receive psychiatric treatment. Relative to the 15 year maximum for the crime he had committed (product tampering and offering false information about a threat), she was lenient — especially considering that he would be eligible for parole in less than a year.

What has happened to Cetkovic since then? It is somewhat of a mystery. There are several recent records of people with his name living in Montenegro (such as a hotel owner), but it is unclear if they represent the same person. Surely, it would be interesting to see if he has preserved any interest in physics. In the annals of Princeton’s accomplished physics department, the story of Dragoljub Cetkovic is certainly one of the most tragic episodes.

Paul Halpern is the author of fifteen popular science books, including The Quantum Labyrinth: How Richard Feynman and John Wheeler Revolutionized Time and Reality