Investigators in Sweetwater County, Wyoming, solved a nearly 40-year-old cold case this week, officially charging a man known as "The Dating Game Killer" with the 1977 murder of Christine Ruth Thornton.

Recent discoveries in that probe give new hope that, someday, authorities may solve Wyoming's most infamous cold case.

In the summer of 1974, the small town of Rawlins, Wyoming, was shocked by a series of murders.

On July 4th, two 19-year-old girls turned up missing after attending the Little Britches Rodeo.

The following month, a 15-year-old girl mysteriously vanished.

Three weeks later, a 10-year-old girl was abducted from the Carbon Country Rodeo.

Four missing girls in seven weeks confirmed the town’s worst fear; a serial killer was on the loose.

Nine years after the crimes, the body of Christy Gross, who had been visiting her friend in Rawlins for Independence Day, was discovered outside of Sinclair, Wyoming.

Although the bodies of the other three girls have yet to be found, authorities have classified their cases as homicides.

Some believe notorious murderer Ted Bundy may be responsible for the crimes. Bundy has been tied to dozens of killings in Utah and Colorado during the 1970s, leading many to believe he may have been involved.

Perhaps the most likely suspect is a man named Royal Russel Long. Long was a truck driver who lived near Rawlins at the time of the crimes.

Long was also a suspect in the murder of two Oklahoma girls in the 1980s, but he was never formally charged. He suffered a fatal heart attack in 1992, while serving time in a Wyoming prison for the kidnapping and assault of two girls from South Dakota.

Although the case remains unsolved, the trail hasn’t gone completely cold. In fact, one local investigator recently launched an effort to tie Long to the murders using DNA. Sadly, having only discovered one of the four victims has made it difficult to gather evidence.