Icebreaker: The Frozen Inland Seas, explores ice breaking and rescue operations of the Coast Guard Cutter Mackinaw as she patrols the frozen inland seas of the Great Lakes. During the harsh northern winters, the men and women of the United States Coast Guard break ice using the mighty Mackinaw Icebreaker. The power of the Mackinaw, the largest icebreaker on the Great Lakes, is legendary. Breaking ice as thick as ten feet, she keeps the shipping lanes open and liberates ships and freighters hauling valuable cargo trapped in the Great Lakes’ icy grip. Her service extends the shipping season on the Great Lakes, which is vital to the American and world economy. Join the crew of the Mackinaw in this in depth documentary about life on a U.S. Coast Guard Icebreaker.