Toward the end of the novel a reporter comes knocking at Gatsby's door looking for a story on Gatsby's parties and his underworld affiliations. This takes place in Chapter 6.
About this time, suspicions concerning Gatsby grow to such an extent that an “ambitious young reporter” attempts to get a statement from Gatsby or some story about this mysterious man’s notoriety.
Throughout the novel, rumors have been reported in dialogue about Gatsby's nefarious connections and questions have been raised about how he has acquired his wealth. Supposed by some to be a cousin to Kaiser Wilhelm and by others to be involved with the people who fixed the World Series, Gatsby is seen by many people to be not only mysterious, but dangerous.
Some of these rumors point to a truth about Gatsby, but many of them are exaggerated. The presence of the reporter marks the extent to which these rumors have grown to such exaggerated proportions as to border on becoming news, as the reporter rather naively suggests.
Stories circulating have to do with an “underground pipe-line to Canada.”