Back in 1993, a disgruntled former employee of Chuck E. Cheese in Aurora, Colorado, hid out in the restaurant's bathroom until closing time, then emerged to shoot and kill three teenage employees and one 50-year-old mother of two.
His latest appeal of his death sentence was just rejected by Colorado's Supreme Court, making his execution a near-certainty and thrusting the case back into the spotlight.
Here's what you should know about the case of dead man walking Nathan Dunlap, the Chuck E. Cheese Killer.
1. Nathan Dunlap Shot 5 People at Chuck E. Cheese
At age 19, Nathan Dunlap, a former Chuck E. Cheese employee, killed the night manager and three teenage employees with shots to the head at the restaurant in 1993. He shot a fifth employee, who survived and identified Dunlap as the culprit.
2. Dunlap Lost His Most Recent Appeal
On Monday, Dunlap's appeal, claiming that his legal defense was ineffective, was rejected by the Colorado Supreme Court. The justices ordered that a date be set for Dunlap's execution.
3. He Was Convicted in 1996
Dunlap, now 38, was sentenced to death by a jury in 1996, found guilty of eight counts of first-degree murder, as well as charges of attempted murder, robbery, theft and burglary.
4. Aurora is a Hotbed of High-Profile Criminal Activity
Dunlap, as well as the two other men who are currently on death row, all committed crimes in Aurora, Colorado, the scene of the Dark Knight Rises movie theater massacre, which killed 12 people and injured 70 others. Prosecutors have yet to decide if they will seek the death penalty against the perpetrator of the July 2012 massacre, James Holmes.
5. Colorado Goes Back and Forth on the Death Penalty
In 1972, the U.S. Supreme Court suspended the death penalty nationwide. Capital punishment was reinstated in Colorado in 1975. Since then only one person, Gary Lee Davis, has been executed in Colorado (1997) after being found guilty of rape and murder.
6. Dunlap Will Continue to Fight to Delay His Execution
Dunlap's attorney, Philip Cherner, says he plans to ask the court to reconsider its decision. If that doesn't work, he will attempt another appeal through the federal courts. However, further appeals are not guaranteed to delay his execution.
7. Dunlap is the Longest-Serving Inmate On Colorado's Death Row
Three of his victims being teenagers, Dunlap has spent more time behind bars than some of his victims spent alive.
8. The Governor Can Pardon Him
In Colorado, the governor has the choice to pardon or change the sentencing of someone on death row. But current Governor John Hickenlooper has expressed his disinterest in overturning the verdict. District Attorney George Brauchler has also said that he is committed to seeing to Dunlap's execution.
9. He Tried To Be Determined Mentally Ill
His petition to the Court of Appeals claimed his defense did not effectively convey his mental illness, but orders also said Dunlap said to a doctor that he would "play crazy as long as I can," and that the case against him was weak.
10. Dunlap Made "Disparaging Remarks" about the Victims
Court orders also make note that Dunlap insulted the victims, saying they meant nothing to him and that he would kill again.