Russell Williams was the commander for Canada's largest airforce base. He flew dignitaries like the Prime Minister and Queen Elizabeth around. He also broke into homes to steal women/girls underwear and took selfies for years until he progressed to rape and murder.
Cody Legebokoff is one of Canada’s youngest serial killers (Age 19/20) - killing 3 women and a teenage girl. When he was caught in Late November 2010 covered in blood, he claimed he clubbed a deer to death because “I’m a redneck, that’s what we do for fun.” The only reason he was caught that night was because of erratic driving and after his explanation the lack of hunting permit in accordance with the Canada Wildlife Act. The blood trail led to one of his victims, and then Legebokoff’s DNA connected him to his 3 previous victims.
Richard Chase was a serial killer who would only go into people’s home if their front door was unlocked because otherwise he “didn't feel welcome.” He believed he was a vampire and thus he could not go into a home if it was locked, which is a part of vampire mythology.
Albert Fish would stick needles into his pelvis when he was masturbating. He would stick them so deep sometimes they would get stuck. When he told this to police, they didn't believe him until they saw the x-ray of needles still embedded in his pelvis. He had children of his own, and was by all accounts a very kind and gentle father, and never even raised a hand on his own kids. He cooked and ate a little girl once and then sent a letter to her parents about what she tasted like.
Robert Hansen would kidnap women and turn them loose in the Alaskan wilderness, where he would then hunt them down like animals and kill them. He didn't have the highest number of victims, but his method of hunting them for sport is absolutely insane.
At the age of 15, Ed Kemper murdered his paternal grandparents. After he came out on parole at the age of 21, he went on to kill six college students, his mother and her best friend. He was also a prolific audiobook narrator and he has several hundred completed recordings to his name. He once buried one of his victim's severed head in his mother's garden as a joke and later remarked that his mother “always wanted people to look up to her.” On one occasion, when he was left alone in a cell with FBI agent Robert Ressler, who was interviewing him, Ed started taunting him, implying that he was going to murder him. Once the guards returned, Ed told Ressler that he was "just kidding."
Ted Bundy helped in the investigation of the green river killer and made a psych profile which ended up being closer to the actual green river killer than the FBI's own psych profile. That was also a huge part of the inspiration for the silence of the lambs. Bundy also tried to masturbate to photos of his crime scene when detective Kepple brought them in, which is why they stopped letting Bundy keep the files.