Glynn Martin is a retired officer from the Los Angeles Police Department and the author of 'Satan's Summer in the City of Angels' about the local community's response to the 'Night Stalker' serial murders. Martin shares his experience as a young cop in the L.A. area during Richard Ramirez's reign of terror with A&E True Crime.

What is evil—and how do we measure it? Is it more evil to abduct and torture a stranger for days before ultimately letting them go, or to fatally shoot a spouse in a fit of jealous rage? We speak to clinical psychologist Dr. Gary Bucato, co-author of the new book, 'The New Evil,' about how he determined what acts are more evil than others and why serial killers aren't all categorized the same way.

Samuel Little murdered as many as 93 women, some almost a half century ago. But all these years later, he still remembers their faces. A&E True Crime spoke with sociology and criminology professor Jack Levin, who explained how serial killers remember their victims and why these details are so important to them.

Serial killer Ted Bundy had a chameleon-like ability to deftly change appearances—whether physically or with the help of costumes and props—which helps explain why the vicious killer was able to evade police for so long.

Kerri Rawson, daughter of Dennis Rader, otherwise known as serial killer BTK, talks to A&E True Crime about her struggle to reconcile the man who raised her with the one who, for years, terrorized her hometown of Wichita, Kansas.

Serial killer Richard Ramirez, otherwise known as 'The Night Stalker,' terrorized California in the mid-1980s with a series of rapes and murders. A number of women who survived his attacks mentioned his rotten teeth, among other details, helping police create a profile of the suspect.

A&E True Crime takes a look back at the horrific crimes of Canadian serial killer and 'Cold Case Files' subject Ronald Glenn West and investigates where is he now.

A&E True Crime explores the details about serial killer Ted Bundy's January 24, 1989 execution and the macabre hoopla, including celebrations and commemorative T-shirts, that surrounded it.

From putting himself on the stand to proposing to his girlfriend in court, we look at some of the most outlandish moments from the serial killer's murder trials.

A&E True Crime talks to experts on Jeffrey Dahmer about his early life and what may have led to him becoming a serial killer.