months, working from opposite ends of the diversion group's small cluster of cubicles in the DEA's concrete tower in Minneapolis, they pulled the names of three RX Limited drugstores off the FedEx account, one each in Minnesota, Texas, and Illinois. With the help of the states' pharmacy boards, they then conducted what looked like routine inspections. On one of the visits, to La Joya Drugs in Chicago, they hit the jackpot: A pharmacy technician happily walked the investigators through the steps they took to fill RX Limited's online orders. RX Limited had provided La Joya Drugs with a free computer, printer, and FedEx supplies, together with a step-by-step manual. The technician would log on to a web- site, download a document containing drug orders, then open a custom program called PCMS. Inside PCMS, which seemed to be software created by RX Limited solely for this purpose, the techni- cian could check off each order as it was filled, then generate the FedEx label and send out the drugs.

That explained how these small pharmacies were able to ship such a huge volume: RX Limited was supplying both the orders and the technology to fill them. But where were the orders coming from in the first place?

Holdren typed the name "RX Limited," together with the Texas mail-drop address, into a search engine and turned up a site called Acmemeds.com. The site looked like a legitimate online drugstore. Calling itself a "trusted online pharmacy since 2004," it featured a stock photograph of a doctor and a note offering "U.S.-LICENSED PHARMACIES, U.S. LICENSED PHYSICIANS, FEDEX OVER- NIGHT SHIPPING." Visitors to the site could search among doz- ens of drugs and place an order using a credit card. If they ran into any trouble, they could call a 24/7 toll-free customer service line, or access a live help chat.

By searching the Web using blocks of text and phone numbers they found on Acmemeds.com, Holdren and Brill would eventually discover hundreds of similar websites, with names like Cheaprx meds.net, Allpharmmeds.com, Buymedscheap.com, Your-pills.com, Speedyrxdrugs.com, All-the-best-rx.com, Ibuymedscheap.com,