O.J., JonBenet, Amanda Knox, oh my! Revisiting notorious crimes hottest trend on TV

O.J. Simpson's "trial of the century" became must-see TV in 1995. 21-years-later, the popularity of two shows about the trial -- “O.J.: Made in America” and “The People v. O.J. Simpson” -- has helped unleash a floodgate of new shows about yet another notorious 1990's crime -- the 1996 murder of JonBenet Ramsey, spawning at least six new series and specials about the cold case.

The latest, a two-hour "Dateline" special on the case, airs Friday night. "Who killed JonBenet?" includes interviews with the 911 operator and two Colorado detectives.

This fall, CBS is airing “The Case Of: JonBenet Ramsey,” a six-hour docuseries including interviews with some of the original investigators and new experts in an attempt to solve the case.

Add to the Ramsey specials a new Netflix series on the Amanda Knox murder trial, plus Netflix's second installment of "Making a Murderer" about the murder conviction of Steven Avery, and it's apparent that true crime shows are TV's hottest genre.

Psychiatrist and FOX News contributor Dr. Keith Ablow says shows about unsolved murders connect with viewers.

“First, human beings are natural storytellers; we want things to make sense,” he explained. “Challenging our minds to make sense of mysteries captivates us—literally, neurologically and psychologically.”

Dr. Ablow says people also inherently seek justice.

“The idea that a killer might go free, or someone who is innocent might be wrongly accused moves us, deep in our psyches,” he said. “Third, human beings, since we are empathetic, actually experience a degree of anxiety and fear about murder, so watching shows about it can allow us to feel that edge-of-the-seat emotion, while we are safely in our living rooms or in theaters.”

But another expert notes making a TV show about a crime is a lot easier than solving one.

“Crime has always been a media fascination,” Dan Gainor, VP of business and culture for the Media Research Center, told FOX411. “I think one of the reasons cold cases have such an appeal is that we have so many tools, so much technology that it’s hard for people to believe we can’t solve every major crime. Unfortunately, real police work is a lot harder than TV.”

Many looking forward to the new shows have also taken to Twitter.