Construction began in 1970 on the Tazara, a 1,860-kilometer line connecting Dar es Salaam on Tanzania's coast to Kapiri Mposhi in northern Zambia's Copperbelt. The film traces why the line exists at all: after the World Bank and Western lenders refused to finance a route they called too risky and economically unviable, China put up roughly $500 million and Chinese and African crews finished it in six years, giving landlocked Zambia's copper exports a path to the sea that bypassed the apartheid-ruled states to the south. Archival footage and present-day train journeys show the 22 tunnels and 320 bridges cut through forest and mountain largely by hand, machete work in country so remote that wild animals posed as much daily danger as the terrain itself. Official figures put the death toll among workers at 160. The documentary rides the modern route through the same national parks the builders once cleared, tracking how a line dismissed as unbuildable became one of postcolonial Africa's largest infrastructure projects.