William Ian Brown did not have a prescription for the single alprazolam (Xanax) pill he was allegedly carrying in his pocket when he was arrested on Sunday. A crime, to be sure, but a minor one. If prosecutors decided to pursue the case -- given that it was a single pill, they might not bother -- the worst outcome would be a short stretch in Lew Sterrett, a modest fine and a misdemeanor conviction.

But that pill wasn't his problem. It was the 550 pounds of alprazolam he and his business partner, Brandon Lynell Gardner, had allegedly just taken possession of near Interstate 35 and Northwest Highway.

According to federal court documents, Brown and Gardner, are both officers of Dynasty Global Systems LLC, a local freight-hauling company. Gardner had arranged a shipment of two pallets from Denver to be delivered to a Northeast Dallas warehouse.

The truck driver assigned to make the delivery didn't know what was on the two pallets, but the presence of a "chalk substance," plus the fact that a "priority delivery" was being sent to an unmanned warehouse, were enough to make him suspicious. So, he contacted the DEA.

He met with federal agents and members of Dallas PD's narcotics unit upon his arrival in Dallas on Saturday. It didn't take long for their drug dog to pick up the scent of Xanax or for the officers to find 550 pounds of pills in vacuum sealed bags. Depending on dosage, that's somewhere between 250,000 and 1 million pills in all.

On Sunday, he made the delivery as planned, although Gardner changed the location at the last minute from the warehouse (which sits just behind the Pump It Up bounce-house extravaganza at Forest Lane and Greenville Avenue, the go-to place for 5-year-olds' birthday parties) to a location near Interstate 35 and Northwest Highway. DEA agents were watching as the deal went down, and they arrested Brown and Gardner as they began to drive away in their U-Haul.

Brown and Gardner both claimed ignorance of the shipment's contents, a story the feds didn't buy. Prosecutors filed criminal charges against the pair on Monday.

Send your story tips to the author, Eric Nicholson.