A Date In Helsinki

First printed in Ellery Queen's Mystery Magazine October, 1982. Reprinted as Date in Helsinki in the anthology Lady on the Case, edited by Marcia Muller, Bill Pronzini, and Martin H. Greenberg, 1988
Selena Mead is reporting on a trade conference in Sweden when she receives mysteriously a plane ticket to Helsinki which she is certain came from Section Q. The strange mission asked of her is to figure out a code from an unknown person played out on a roulette wheel detailing delivery dates of an arm shipment.