The last year or so has been a great time to be in the oil-refining business. Thanks to problems getting crude oil from new shale oil plays to big markets like the Gulf Coast, the price for certain crudes in the U.S. have sold at a steep discount to foreign crudes. Today, though, that pricing advantage is starting to fade as the price for West Texas Intermediate, the domestic benchmark, is not within $6 to $10 of foreign spot prices.

This is particularly concerning for refiners in the mid-continent region, who were seeing the price differential between a barrel of crude and a barrel of refined products as high as $35 only a couple of quarters ago. Does this mean the end of the mid-continent advantage? Tune into the video below as Fool.com contributor Tyler Crowe looks at the prospects for these refineries and three companies he sees will be most affected.