 Luminol in itself won't usually solve a murder case. It's only one step in the investigative process. But it can reveal essential information that gets a stalled investigation going again. The search for the presence of blood at a crime scene is normally done by close visual examination. The possibility exists, however, that blood may be present in amounts too little to see with the unaided eye, or that the blood at the scene had been cleaned up prior to arrival of the crime scene team. Typically, Luminol only shows investigators that there might be blood in an area, since other substances, including household bleach, can also cause the Luminol to glow. In some cases, Luminol leads investigators to more evidence. For example, if Luminol detects trace amounts of blood on a carpet, investigators may pull up the carpet and discover a lot of visible blood on the floorboards below. By applying Luminol to a linoleum floor, an attempt to clean up blood is apparent. Normal photograph of the area before taking the Luminol photograph. This completed Luminol photograph shows the location of blood stain. Experienced investigators can make a reliable identification based on how quickly the reaction occurs, but they still need to run other tests to verify that it is really human blood. Hidden blood splatter patterns help investigators locate the point of attack and even what sort of weapon was used. A bullet makes blood splatter very differently than a knife does. Luminol may also reveal faint, bloody shoe prints, which gives investigators valuable information about the assailant and what he or she did after the attack. Chemical enhancement of footwear impressions in blood-on fabric. Map of Luminol traces found in Kertcher and Knox apartment, proof of a cleanup after the murder of Meredith Kertcher. One problem with Luminol is that the chemical reaction can destroy other evidence in the crime scene. For this reason, investigators only use Luminol after exploring a lot of other options. It is definitely a valuable tool for police work, but it's not quite as prevalent in crime investigation as presented on some TV shows. The police don't walk into a crime scene and start spraying Luminol on every visible surface. A case solved with the help of Luminol. Aspiring filmmaker Mark Twitchell has been found guilty of first-degree murder and sentenced to life in prison for bludgeoning, stabbing and dismembering a stranger for purely experience of killing another person to make a more authentic serial killer movie. Twitchell, 31, used an online dating site and disguised as a woman named Jen to lure Altinger, 38, to a rented garage in South Edmonton on October 10th, 2008, before killing him. A happy face of Atlinger, heading to a rented garage where he supposedly thought to meet the woman he was chatting with online, but instead met his brutal fate by the hands of a narcissistic person. At first, officers found nothing inside, until a chemical called Luminol was sprayed on the floor. A giant pool of blue light suddenly glowed in the dark. Detectives began a search of the home of Mark Twitchell, the filmmaker renting the garage and found this modified hockey mask in his basement. The mask was from a horror movie about a serial killer who lures men off dating websites to his suburban kill room. Police found this laptop in Twitchell's trunk and the deleted files, a document titled SK Confessions. The first lines read, This story is based on true events. The names and events were altered slightly to protect the guilty. This is the story of my progression into becoming a serial killer. Police placed Twitchell under 24-hour surveillance. During their investigation, they learned that he is a devoted fan of the Showtime series Dexter about an avenging serial killer. Twitchell even posed as Dexter Morgan on Facebook, a photo of Johnny Atlinger's blood and Mark Twitchell's car trunk. Investigators also found a knife in Twitchell's car with blood on both the sheath and knife. Police believe that Atlinger was hit over the head with this pipe shortly upon entering the darkened garage. He was then stabbed to death. Twitchell then dismembered Atlinger on this table inside his garage. Police evidence tags point out blood spots, some visible to the naked eye. The evidence found by police matched the descriptions and SK confessions. One passage spoke of the killer trying to burn Atlinger's remains in a barrel. Police found a burned barrel inside Twitchell's garage. Police even found outlines of a barrel burned into the grass of Twitchell's parents' backyard. Twitchell dismembered Atlinger's body and dumped his remains in this north Edmonton sewer. Michael C. Hall, the actor who portrays Dexter, was informed of Twitchell's obsession. He said it was a troubling thing to consider. I don't think it is a primer on serial killing or it advocates the lifestyle. I would hope that people's appreciation was more than some sort of fetishisation with the kill scenes. The writer of Dexter also declared that reading Dexter will not make you a killer. If you are not already capable of killing another human being in a cold, cruel, deliberate way, no book ever written will make you capable of doing so. There are no magic words that will turn you into a psychopath. Joni Atlinger left behind a loving mother, brother, nephews and many friends.