Hiram Holliday, a small, mild-mannered newspaper proofreader, saves his publisher from a disastrous libel suit when he finds a misplaced comma. The grateful publisher rewards Hiram with an around-the-world tour and sends a reporter to document his adventures. Before the pair can leave port, Hiram becomes cast in a supposed espionage film and surprises his foes with amazing physical skills.
On the first leg of their around-the-world tour Hiram and Ainslie make landfall in England prior to traveling to Scotland. Immediately after arriving the two men become involved with a murder, a stolen gem and a poisonous snake.
During his visit to Scotland, Hiram is convinced to impersonate the King of Rovaki who looks exactly the American tourist. Hiram soon discovers the reason for the identity change, after someone attempts to kill him.
After finding a mysterious message in the hollow handle of his umbrella, Hiram finds himself chased by foreign spies and the Paris police. In order to throw his pursuers off his trail, Hiram performs in a circus as a trapeze artist and an exotic dancer.
While visiting a small but strategically important European kingdom, Hiram is accidentally selected as the nation's new monarch. He must defeat an evil nobleman and his henchmen in order that the proper ruler be selected.
While searching for evidence of one of his ancestors, Hiram is shipwrecked on the African coast. Hiram meets an evil Berber sheik and a lot of men who look remarkably like the globetrotting proofreader.