USDA scientist Mark Carleton appears to be traveling on some kind of junket as wheat farmers face disaster from drought, frost, and diseases. But in Russia, he finds a variety of wheat that's resistant to drought. He brings it home, and the Kubanka strain is an instant hit with the farmers. But the farmers that had been singing his praises are cursing him at harvest time. The wheat is much harder than the popular but fickle spring wheat, and millers will not accept it because it would cost them millions to retrofit their mills. Carleton tries to persuade them, and to increase demand for macaroni (the best use for the resulting flour), but to no avail. The following year, a severe blight of black rust hits, wiping out the spring wheat crop. But the Kubanka durum is resistant to the blight, and the millers, seeing no alternative, accept the wheat. It becomes a standard. Carleton himself, however, dies in poverty. (The film omits Carleton's other important crop introduction, Kharkof [Turkey] red winter wheat.)