Murder in Delphi

"he appeared like a normal guy... "
This is what locals say about the 50 year old murderer, who married with a daughter.
Who would have thought an ordinary store employee in Indiana would have a hand in the shocking murder of two teenagers?
How did he do it?
Did he have help?
Are the girls his first victims?
5 years ago, two best friends, Libby and Abby set out hiking in Delphi, Indiana.
They never returned.back to their families.
What really happened?