Little Dick is ambitious to be a detective like his father. He reads many detective tales and acts out the stories with his playmates. His father sees him at his games, gives him a badge, and promises to make him a real sleuth. The next day Dick hears his father called on a big Italian murder mystery case. While playing with the boys, he sees a dark-browed foreigner rush out of a house and race down the street. This looks suspicious to Dick; he gives pursuit. The Italian dashes out of a drugstore with a bottle labeled "poison." Dick sees him hand it into a room and then wait anxiously about outside with several villainous-looking companions. Leaving two of his little pals to stand guard, Dick rushes to the police station and returns with an automobile full of police. They seize the Italians, then discover that the Parisi family is celebrating the arrival of a new baby.
—Moving Picture World synopsis