The Iranian Crown Jewels. For years they rested in the vaults of the Markasu Bank in Tehran, where they backed Iran's legal tender, but when the National Emergency Council governing Iran in mid-1996 abandoned Tehran and retreated to Esfahan, they toll the Crown Jewels with them.
In the first half of 1997, the NEC elected to move again, this time from Esfahan to Shiraz. The Iranian Crown Jewels were left behind just long enough for preparations to be made to secure them in Shriaz. Other considerations, such as the fact that even Shiraz became cut off byu further Soviet advances, soon occupied the Council's collective mind.
But as Esfahan looked in imminent danger of falling to the Soviets, a desperate mission to move the Crown Jewels was launch. The mission never returned; Esfahan was quickly captured by Soviet forces; and the Jewels were lost in the shuffle. The Soviets assumed the NEC had them. The Council believed that they had been captured by the Soviets. But rumors began to circulate that the jewels had simply disappeared.
In King's Ransom, the players learn that someone has found the Crown Jewels and a desperate rave begins to beat the KGB to the jewel's hiding place.