The office of mining engineers and partners Larkin Moffatt and Charlie Storrs is robbed. Storrs accuses Moffatt of complicity with the robbers and fires him. He also asks all major mining companies in the region to avoid hiring Moffatt. Unemployable, Moffatt opens his own small independent assay office in Silver City. His first client, Candace Surrency, leases a mine from the greedy R. R. Jarboe, owner of several mines. Candace Surrency and her father have invested all their funds in the mine lease which is due to expire in 12 days, reverting the mining rights back to its owner, R. R. Jarboe. So far the mine has been dry but the Surrencys have hired Moffatt to do another assay on the latest batch of ore. Moffatt finds silver in large amounts in the test batch, making the Surrencys rich. News of their silver strike spreads fast. Mine owner R. R. Jarboe refuses to extend the mine lease to the Surrencys who won't have enough time to extract and process the silver ore during the remainder of the lease. R. R. Jarboe is sure to benefit from the silver strike once the mine reverts to him. Desperate, the Surrencys ask Moffatt to become the mine's foreman and use his expertise to extract and process the silver ore within the remaining 12 days of lease rights. Aware of R. R. Jarboe's power Moffatt refuses to get involved but changes his mind when noticing Jarboe's ruthless sabotage tactics against the Surrencys. Moffatt and Candace Surrency fall in-love. Unfortunately, Moffatt's old boss and former partner Charlie Storrs shows up in town to buy this particular mine from owner R. R. Jarboe.