School is in session, and TikToker Savannah (@ohsavannahmarie) is kicking off her second day of the fall semester with what might just be the most fascinating class in the course catalog.

In the morning, she went to her financial analysis class. Then, she went to her class about serial killers. It was every bit as exciting as she thought it would be.

The professor was super cool and had met John Wayne Gacy before.

John Wayne Gacy was an American serial killer who tortured and murdered at least 33 young men and boys between 1972 and 1978.

Her professor has actually interviewed Gacy five or six times, each session lasting six to eight hours at a time. He was even invited to visit Gacy in prison.

According to her professor, the most terrifying thing about John Wayne Gacy was that he was not scary at all. He was funny and gave off "favorite uncle vibes."

So, it was easy for him to lure boys in.

After Gacy was executed, a medical examination was done on his brain. Shockingly, there was nothing wrong with his brain. Every test result came back normal. There were no anomalies to explain his actions.

In the comments section, some TikTok users described their own experiences and knowledge about prolific serial killers.

Des Plaines Police Department - pictured above is John Wayne Gacy in his mugshotDes Plaines Police Department - pictured above is John Wayne Gacy in his mugshot

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"I took a serial killer class in college, too. My professor actually helped catch a serial killer. It was one of my favorite classes. So interesting and informative. He said the same thing about Gacy; he was a people person and very laid-back. Everyone felt comfortable around him; he just had an extremely evil side hobby," commented one user.

"John Wayne Gacy was very popular in his neighborhood. He loved dressing up as a clown at parties for laughs and was involved in politics in his community. He very much knew how to play that character to assimilate into society. That's how he got his victims to trust him," stated another.

"My mama was friends with Jeffrey Dahmer in the '80s, and she said the same thing about him. He isn't scary at all; he acts so normal. No one knew he was crazy," chimed in someone else.

@ohsavannahmarie

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