The CCGS Henry Larsen is a Canadian Coast Guard icebreaker built to smash through ten-foot-thick frozen slabs in the North Atlantic, and this film follows her crew through a season of high-stakes missions. Cameras aboard the ship and her onboard helicopter capture the work of freeing ice-locked vessels and keeping remote Newfoundland communities supplied when winter seals off their normal routes. The centerpiece is a major winter storm that threatens to cut off small coastal settlements entirely, forcing the Larsen and her crew to push the ship and its equipment to their limits to keep supply lines open. Interviews with officers and crew explain how the vessel's reinforced hull and engines are engineered to survive sustained ice impact, and the footage shows the physical toll that constant collision with pack ice takes on both machine and men. It is a close look at the unglamorous, dangerous work of arctic and subarctic maritime rescue, told through the people who do it for a living.