Paris plumber Elmer Tuttle is enlisted by socialite Patricia Alden to help make her lover Tony Lagorce jealous. With the help of his friend Julius J. McCracken, and through the high society contacts he has made through Patricia, Elmer hopes to find financing for his latest invention, a pistol with a target-illuminating light. Comic complications ensue when Elmer's effort to interest a military leader is misconstrued as an assassination attempt.