In 1975, Glenn was a civilian employee at Fort Carson, a United States Army post in El Paso, Colorado. There I met Michael Corbett, a soldier, and together they embarked on a series of gruesome murders. First, they kidnap Daniel van Loon, a cook who has quit his job, with the intention of robbing them. After murdering her, the killers fled with the entire 50 cents. A few days later, the two kidnap another soldier, whom Corbett bayonets to death.
Two weeks after their killing spree began, Glenn, Corbett and two other men tried to rob a Red Lobster where Karen Grammer worked, but failed to steal any money. Fearing that Grammer would be able to identify them, they abducted her and took her to their apartment where they raped her repeatedly. They later said they would take her home, but instead dropped her off at a trailer park. Before she could escape, Glenn stabbed her several times, including in the throat. She managed to knock on a trailer door, but no one was home and she suffocated.