A fur trapper catches another trapper trying to steal his furs. He stops the thief, but later on the furs are stolen anyway. Rin Tin Tin Jr. tracks down the thief to try to get the furs back.

Rin-Tin-Tin's first sound feature, in which he plays an abused dog recused by a young girl in the far north.

The Laguna Dam is to be built in Arizona to supply water to desert-land unfit for cultivation or stock-raising. Rival companies bid for the building contract, which leads to violence and danger for Bob Owen and his dog Satan.