 On February 20, 2013, a payment processor called Endstage noticed something unusual. Debit cards were withdrawing thousands of dollars at a time, far beyond the normal limit. Someone had hacked into Endstage's system and raised the withdrawal limit, letting millions of dollars flood out of accounts across 24 different countries. By the time Endstage regained control of the system the next day, more than 26,000 transactions had gone through for $40 million. That's more than double the largest cash robbery in U.S. history. The heist was organized by a crew of hackers in Turkey, Romania, and Ukraine. They were the ones breaking into Endstage and raising the limits. But how'd they get the cards in the first place? Pulling off a heist this big require a global network of debit card thieves that's still in existence today. Stealing ATM cards is easier than you think. All you need is a PIN code and a copy of the magnetic stripe. But that stripe is the same magnetic encoding that's on a simple cassette tape. That makes it easy to copy and easy to steal. You can even do it with a cassette player. Thieves usually steal that data by putting a skimmer over an ATM's card slot and planting a nearby camera to capture the PIN code. Once they have that data, they can turn a cheap hotel key into a copy of the ATM card and head to an ATM. The big question for criminals is how much money can you make off each card? You usually only get one withdrawal before banks pick up on the fraud. So the big problem is that withdrawal limit. With the Turkish hacking crew on your side, that goes from $200 to over $1,000, easily worth whatever cut the crew is taking. But that loose network also gave investigators a clear path for tracking the group down. Police arrested one of the cashers after using a hacked card and ATM in Brooklyn. He led them back to the rest of the group. And earlier this year, one of the crew, a Turkish hacker named Erkan Fintikoglu, pled guilty to computer intrusion, conspiracy, and other charges, which could add up to as much as 57 years in prison. The rest of the group is still at large.