With the end of the ice road fast approaching, the Ice Road Truckers are sprinting to the finish. But they've got obstacles. A polar bear standoff at Prudhoe Bay tables the plans for oil production and ties up Carlile's loads at the most crucial time of the season.  A veteran trucker's calculated risk puts his life and livelihood in jeopardy. One rookie's sent packing as the other picks up the slack.  And the Dalton's favorite daughter gets her groove back.