Undercover Agent U.C.E. 4599

This week, State Senator Leland Yee was one of two dozen people arrested by the FBI in a Bay Area sting. Most of the headlines have focused on Yee and his relationship with a one-time gangster known as Raymond “Shrimp Boy” Chow. But there’s another figure who played a big role in this story: “U.C.E. 4599.” Those initials are short for “Undercover Employee.” That’s all we know about the identity of the undercover FBI agent who cracked the case. But the details of his investigation are as surreal as everything else about this sting.