Based on a play by Aben Kandel, a promoter organizes an artificial rubber company and sells stock.
Mike Donoghey (Frank McHugh) and Ginsburg (George Sidney) find Gar Evans (William Powell) passed out drunk in a speakeasy owing $108. Ginsburg pays it, and they give Evans a Turkish bath, shower, and a massage. Ginsburg wants to make artificial rubber out of sewage. Mike says that Evans is the greatest promoter. Evans wants 51% and says Ginsburg needs $25,000 front money. Evans sends Mike to explain to Francine (Evelyn Brent). Evans gets the name Golden Gate Artificial Rubber Co. put on the building and sells the landlord stock. Francine is engaged to a South American. Evans makes Clifford Gray (Guy Kibbee) president, because he looks the part; he puts a towel salesman on the board, because his name is Vanderbilt. He hires Helen (Evalyn Knapp) as his secretary and hopes she'll stay single to work nights. Her boyfriend Geoffrey will write publicity.
Francine tells Evans it's all over. Evans teaches a Dynamic Personality class with an inspiring speech about Columbus, the Wright brothers, and the Warner brothers pioneering vitaphone. Men on telephones sell shares. Evans kisses Francine. An attorney for the rubber interests, Banks, wants to see their patent. Ginsburg can't find his inventor. Francine doesn't believe Evans' latest excuse; so he gives her his 51% of the stock. Helen gives Evans $300 for stock and kisses him. The attorney general serves an injunction against selling stock, and Francine walks out.
The inventor Rudolph appears, and Hackett of the Better Business Bureau meets him. Evans realizes he sold Rudolph a phony chemistry degree in Detroit. At the lab Rudolph tries to make rubber. Evans tells the press the rubber industry is against him and invites them to send their scientists to inspect the process. Rudolph says he could make hens lay colored Easter eggs, and they realize he is crazy. Evans' lawyer tells him to leave in order to avoid being arrested. Banks comes back and offers to buy the stock and give Evans a $100,000 bonus to remove the nuisance. Evans agrees and tells Mike to get the stock certificate from Francine. Helen and Geoffrey are getting married. Evans and Ginsburg go to the boat to catch Francine. Evans asks her to marry him, and Ginsburg finds the certificate in her trunk. Evans and Francine are going to marry right away; but Mike gets Evans interested in new projects with gold or spruce.
This comedy satirizes stock-selling and indicates why some stocks may soar and then plunge. Evans even strings along his fiancée, and at the end she appears defeated by his continuous scheming.