Only one railway line crosses Canada's tundra to Hudson Bay, and this film rides it end to end. The journey starts in Winnipeg, Manitoba's multicultural capital, then pushes north through prairie farmland that replaced old bison range, into swampy coniferous forest, and finally onto treeless Arctic tundra. Along the way the film stops with First Nation communities who depend on the line to reach their reserves, and who bought and repaired sections of track themselves after floods washed out the route in 2017. After 1,700 kilometers and roughly 45 hours aboard, the train reaches Churchill, a town of about 900 people where polar bears gather each autumn as the bay begins to freeze and the aurora borealis lights up the night sky. Shot largely from the carriage window and at stops along the route, the film lets the landscape and the people who live beside the tracks carry the story, with little need for a driving plot beyond the trip itself.