Maybe they were singing "Breaking the law, breaking the law (yeah!), breaking the law, breaking the law," by Judas Priest.
On Friday, two elderly German men slipped out of their nursing home to attend the world's largest heavy metal festival at a nearby town, police said.
The men somehow toddled off to the four-day Wacken Open Air festival, which took place over the weekend in the northern German town of Wacken and draws upward of 75,000 metalheads.
"According to public radio broadcast NDR, nursing staff contacted police after they noticed that two of the home's residents were missing," The Independent writes.
The pair were found at the festival at 3am in a state that police spokesperson Merle Neufeld described as "disoriented and dazed".
"They obviously liked the metal festival," she continued. "The care home quickly organised return transport after police picked them up."
Artists performing at this year's Wacken Open Air included Judas Priest, Danzig, Red Hot Chili Peppers and In Flames.
The men were reluctant to leave the four-day festival "so police escorted them home with the help of a taxi and a patrol car."
Rock on, old dudes!