After the works party of Midlands engineering firm Lang's, the Chairman, Gustavus Lang, collapses and dies. His power-crazed half-brother Walter attempts to seize control of the company by purchasing Gustavus's shares but is swiftly rebuffed. Jack Partridge, a lathe operator, begins a romance with Rosamund, Walter's nubile young daughter, after dancing with her at the works party. Walter agrees to a collaboration with another company, only to realize that the rival concern intends to swallow up Lang's. Thwarted and outmanoeuvred, Walter is then told that Rosamund has gone on holiday with Jack and sets off to confront them...