The Blue Paint Killer

• Janet Kent (1987) – an art student who was taught by, and dated, Cody Lewis
• Marcia Reese (1987) – another student at WLVU
• Charlene Roth (1988) - killed by John Mathers executed 15 years later
• Debbie Reston (2002) – killed on the day of John Mathers' execution
• Jonathan Avery Haywood (III) (2004) – killed by mistake due to resemblance to Kaitlin Rackish
• Kaitlin Rackish (2004) – a student of Cody Lewis

The killer applies blue house paint to railings in the fictional Western Las Vegas University campus; he chooses the railings because they are near a water fountain. Motor oil is mixed into the paint to slow the drying process. He waits for the female victim to touch the railing and then, with the victim attempting to wash the paint off her hand at the water fountain, he attacks her, binds and gags her, bundles her into a van and drives away from the site. He then stops the van outside an erotic boutique and sketches while his victim pleads for mercy. He draws her while he sits in the driver's seat looking at her through the rear view mirror as she struggles in the back. He then sexually assaults her before strangling her to death. After he kills his victim, he dumps her, in a black garbage bag, around Las Vegas and sells his sketches to the owner of the boutique.

The exception to this M.O. is Jonathan Avery Haywood III, killed in "What's Eating Gilbert Grissom?". As Haywood is mistaken for Kaitlin Rackish, the killer does not assault or sketch him and disposes of the body by feeding it into a wood chipper on campus.

Kevin Greer worked at the WLVU's campus from 1983 to 2004, and was the only employee of the press to have worked there for more than 10 years when he was caught. He also had a job writing explicit comic books for a sex shop, under the pseudonym of Zippy T. He commits the first murder at the approximate age of 16 prior to the events of "The Execution of Catherine Willows", estimated from the show's chronology to be in 1987. In 1988, John Mathers is arrested and placed on death row for 15 years; in that time Greer stopped his killing spree, so that Mathers would die and take the blame to his grave. On the day of Mathers' execution, Greer kills his fourth victim, Debbie Reston. Although he intends to kill one victim every year on that day, he does not do so in 2003 because unsuccessful LASIK surgery had temporarily damaged his eyesight (he elected to have the surgery because Debbie Reston broke his glasses in a struggle). The following year, however, he kills Jonathan Haywood, mistaking him for his intended target Kaitlin Rackish because Haywood had long hair and Greer's poor post-LASIK night vision led him to mistake Haywood for a woman. He later tracks Kaitlin down and kills her, but the evidence that he leaves behind at the crime scene (photocopier toner from the WLVU press) leads to his arrest.

After SWAT raids his house, Greer leaves a phone message saying that he would be waiting for Grissom at the police station. When Grissom and Brass arrive, Greer greets them as "Gil" and "Jim", and taunts them about their search. Greer then promises to lead the officers to the location of a sixth victim, Brit Mosscoe. However, this is a ruse (Brit Mosscoe is an anagram of "Miss October", from a calendar hanging in Greer's garage). He asks to go to the bathroom before he leaves, and although an officer escorts him into the facilities, he goes unattended into a cubicle. After Sara Sidle calls Catherine to inform the others of the deception, Grissom and Brass break into the cubicle and find Greer with a black plastic bag tied around his head. They tear the bag off and attempt CPR, but Greer is already dead.

Returning to the interrogation room, Grissom finds a drawing which, when folded, reveals a picture of Grissom and the word "goodbye".

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