“Captain March tells me that you were his crew on Federal Airlines Flight Seventeen, New York to Tampa, yesterday, February seventh.”

The copilot and the two stewardesses nodded automatically.

“Flight Seventeen,” Mr. Quayle continued in a droning voice, “was carrying an especially valuable item of cargo. A crate of antique gold coins from the National Numismatic Museum in New York consigned to the Royal Palms Hall here in Tampa. These coins were to have been put on display next week during the Gasparilla Festival. It is impossible to estimate the value of this shipment. I can only say that it was priceless.”

Mr. Quayle looked at his audience in silence for a long moment.

“When that crate was delivered to the Festival committee at the Royal Palms, it appeared to be exactly as it was when it left the museum. But when the committee members opened it, it was found to contain, not the gold coins, but an equivalent weight in iron-and-steel scrap.”

Johnny and Cathy gasped. Vicki looked at Captain March. His eyes were impassive. Naturally, she thought, he had been told about this before the rest of the crew.

“Only two possibilities have occurred to us,” the FBI man went on, “as to how the theft could have been accomplished. One: the crate could have been opened, the gold removed, and the scrap metal put in its place. Two: the crate of scrap could have been substituted for the crate of gold somewhere en route.”

Again he paused to let his words sink in.

“As to the first possibility, there was no sign of tampering. As to the second, the crate undoubtedly had been packed and labeled at the museum in New York. The label was genuine.”

Again Vicki noticed that Cathy and Johnny were listening in breathless silence.