While scanning the shortwave radio bands recently, I discovered a station broadcasting five-digit numbers in Spanish. Each number was repeated twice before a new one was broadcast. It was a little strange, but I figured I had stumbled onto the Cuban Lotto numbers station. Then last night I picked up a similar broadcast in English. It lasted about 25 minutes, then ended abruptly. A fellow shortwave enthusiast says these “numbers stations” are a big mystery and may somehow be tied into the CIA or drug smuggling! The FCC and CIA were no help, so I turn to you. –Michael Pettersen, Chicago

Best of Chicago voting is live now. Vote for your favorites »

Cecil usually hates to encourage conspiracy buffs, but in this case there doesn’t seem to be much choice. There are dozens of “numbers stations,” some of which have been in business for decades, yet no government or private agency has ever acknowledged them. The stations broadcast in a variety of formats (three, four, and five digits, etc) in languages ranging from English and Spanish to Czech, Korean, and Serbo-Croatian. The voice is often female and its unchanging inflection suggests that it may be machine-generated, like those wrong-number recordings used by the phone company.

Clearly the time has come for one of the Teeming Millions with time on his hands to get a job with the CIA, find out the whole story, and then betray the appropriate nation by giving us the secrets. (I’d do it, but I’m tied up this week.) If they catch you, of course, you’ll probably get the chair, but hey, you can’t make an omelet without breaking some eggs. For more details, see Big Secrets by William Poundstone (1983).