When our mice arrive in Trinidad, cousin Simone introduces them to Melanie Monbrun whose parents own a sugar cane plantation. That night, at the annual masquerade ball, everyone is frightened by an appearance of The Midnight Robber! He warns Melanie's parents not to cut their sugar cane- or else. The lights go out and when they come back on Simone's priceless necklace has been stolen! Our mice find out there are TWO Midnight Robbers and one is none other than Notail Nogoodnik. When the Monbrun's discover their precious sugar cane has been stolen, their neighbor Mr. Warner offers to buy their land. Emily and Alexander must orchestra the appearance of a THIRD Midnight Robber- Melanie herself- in a desperate attempt to stop the sale of the land- but they're too late- the deal has been signed. When Warner's dog chases Notail Nogoodnik out of town, the donkey Emily is riding gets frightened and kicks something strange in the Monbrun's field. Suddenly, a gusher of oil bursts forth! It rains down on Warner's agreement, reducing it to paper pulp. Thanks to the mice, the Monbrun's have their plantation back AND they've struck oil!