On a cool, dark November night in 2002, 20-year-old Josh Guimond walked out of a party at a friend’s campus apartment in Collegeville, Minn., and vanished.

Now, 15 years after the St. John’s University junior disappeared, authorities have no more of an idea of what became of him than they did when he was first reported missing.

But investigators hope publicity surrounding this month’s anniversary of his disappearance and a fresh look at the case will drum up new tips to help solve the mystery.

A Stearns County sheriff’s detective continues to investigate the case and, at the request of Guimond’s family, said he plans to ask another Minnesota law enforcement agency to review it soon. State investigators also are releasing an updated age-enhanced sketch of Guimond, who would now be 35.

“We believe we can solve it through hard work and a little bit of luck,” said Stearns County Lt. Vic Weiss, who oversees the Sheriff’s Office investigative unit. “That case is so open as far as possibilities — whether he walked away, whether he was abducted, whether he was killed. We don’t know why he disappeared.”

Guimond, a captain of the school’s mock trial team, had ambitions to go to law school and run for a legislative seat after graduating. But on Nov. 9, 2002, he left a party on campus around midnight and disappeared without a trace.

With no DNA evidence and people’s memories of that night fading over time, Weiss said it gets harder with each passing year to solve the mystery. The agency hopes renewed publicity surrounding the anniversary will again raise public awareness and generate tips that might lead them to Guimond.

“Someone has a critical piece of information,” Weiss said. “Most times it’s something from the public … that pushes the case forward.”

The state Bureau of Criminal Apprehension is assisting in the investigation, which is one of three unsolved death or missing person cases in Stearns County and one of 82 missing person cases in Minnesota.

“It’s important for those of us close to Josh … to make sure he isn’t forgotten,” said Nick Hydukovich, who was Guimond’s roommate and is now a criminal prosecutor in Washington County. “It’s frankly strange a person could disappear and 15 years later, there’s no evidence. Josh was a real person who had incredible potential. Everyone is desperate to find out what happened.”

In the hours and days after Guimond vanished, more than 100 National Guard soldiers combed the prairies and woods near the St. John’s campus. Dive teams searched nearby Stumpf Lake while a State Patrol helicopter, search dogs and hundreds of volunteers, including students from St. John’s and the nearby College of St. Benedict, scanned the fields.

None of it led them to Guimond.

While Guimond’s family and friends suspect foul play, authorities have yet to find evidence that a crime was committed, Weiss said.

“It’s incredibly frustrating,” said Lisa Cheney, Guimond’s mother, adding that she hopes new investigators at Stearns County “are really looking at it again and looking at it hard.”

On Friday, as they have done each year, Cheney and Guimond’s father, Brian Guimond, joined Josh’s former classmates at a church prayer service in their hometown of Maple Lake, Minn.

“I want everybody to remember he’s still missing,” Cheney said. “Someone’s got to know something.”

Anyone with tips on the case can call the Stearns County Sheriff’s Office at 320-259-3700.