The Nancy Drew Mystery Stories is the long-running "main" series of the Nancy Drew franchise, which was published under the pseudonym Carolyn Keene. There are 175 novels — plus 34 revised stories — that were published between 1930 and 2003 under the banner; Grosset & Dunlap published the first 56, and 34 revised stories, while Simon & Schuster published the series beginning with volume 57.

The Password to Larkspur Lane is the tenth volume in the Nancy Drew Mystery Stories series. It was first published in 1933 under the pseudonym Carolyn Keene. The actual author was ghostwriter Walter Karig in his third and final Nancy Drew novel and his final appearance for the Stratemeyer Syndicate. Due to Karig's death in 1956, this book and his other two Nancy Drews, as of January 1, 2007, have passed into the public domain in Canada and other countries with a life-plus-50 policy.