Grand Duke Leonid of Russia is in Washington to sign a commercial treaty on behalf of the Tsar.But this larger-than-life aristocrat has read too much Fennimore Cooper and wants to visit the West.The US government is forced to agree to his whim-but wisely chooses Lucky Luke to escort him to the cattle capital of the West: Abilene.A good thing, too, because the Russian Grand Duke encounters real American desperadoes on his visit!