The Carrollton Police Department is are asking for the public's help in solving a case that happened more than 20 years ago.
Two teenage girls, Stacie Madison and Susan Smalley, vanished in March 1988. Their disappearance remains a mystery.
Sgt. Joel Payne said investigators reopened the case two years ago, following up on every lead.
"You get to know these girls and realize that these are very typical, late '80s teenagers, getting ready to graduate high school and go to college," Payne said. "We could paper the building with the number of leads and information that came in, but unfortunately, nothing led to a conclusion."
Police said a group of pictures could be the missing piece to this puzzle.
"We are down to a last grouping of things that really don't make any sense to us, and this [the photos] is one of them," Payne said. "Who are these people? They may be nobody significant, but we would like to talk to them."
Authorities are not calling the men in the photos suspects, simply people they need to identify and talk to.
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"These people knew these girls, and they knew them relatively close to when they disappeared," Payne said.
He's asking anyone who thinks the people in the photos look familiar to contact the Carrollton Police Department.
"I am convinced somebody out there knows what happened to these girls," Payne said.
Anyone with information should call the Criminal Investigation Division at 972-466-3300.