Ted Kaczynski was just 17 years old when he signed up for a Harvard psychology study in 1959. The young math student joined 21 other undergraduates in a three-year project led by Henry Murray, a Harvard professor who studied the connections between personality and stress.

Kaczynski would later become the Unabomber, murdering three people and injuring 23 others in a series of bombings that lasted from 1978 to 1995. Netflix’s new film Unabomber puts the experiment back in the spotlight. What happened in Murray’s lab is well documented, but what it did to Kaczynski is harder to pin down.

Here’s what to know about Murray and his controversial Harvard experiment.

Who Was Henry Murray?

Born in 1893 in New York City, Henry Murray was trained in medicine and biology. He graduated from Harvard with a degree in history in 1915, and pursued further education for eight more years. He had an MD from Columbia University, an MA in biology from Columbia, and a PhD in biochemistry from the University of Cambridge.…