Episode 35 of "Criminal Minds"
s02e13 No Way Out

Gideon and the BAU team go head to head with a sadistic serial killer who has tortured and killed more than 100 people in over 30 years. When the BAU locates the alleged serial killer in a remote desert diner, the local authorities are eager to take action, but Gideon insists that they wait when it becomes evident that the murderer is keeping another secret from them. As Gideon and Morgan attempt to ply information out of the suspect, the rest of the BAU team studies the killer's tracks to try and uncover what keeps him coming back to the same isolated town year after year.