British army sergeants Ballantine, Cutter and MacChesney serve in India during the 1880s, along with their native water-bearer, Gunga Din. While completing a dangerous telegraph-repair mission, they unearth evidence of the suppressed Thuggee cult. When Gunga Din tells the sergeants about a secret temple made of gold, the fortune-hunting Cutter is captured by the Thuggees, and it's up to his friends to rescue him.