The revealing history of Birkenstock sandals

It's proof of popularity that the German footwear brand Birkenstock never wanted. In the fight against fakes, the shoemaker has been sending teams of undercover investigators with hidden cameras into what they say are counterfeiting factories.

Birkenstock's CEO Oliver Reichert is aggressive. "We don't just punish the marketplaces or the resellers. We really go to the factories. Turkey, Philippines, China, wherever."

"Sounds like you're running special ops," said correspondent Seth Doane.