The film stars Bonita Granville, John Litel, James Stephenson, Frankie Thomas, Frank Orth and Helena Phillips Evans.

[1][2][3] Wealthy Mary Eldredge (Helena Phillips Evans) decides to donate $250,000 (in 2020 purchase-power that would be $4.5 million) to her alma mater, where teenager Nancy Drew (Bonita Granville) is a student.

When Mary doesn't deliver the check to the lawyer Carson Drew (John Litel), Nancy's father, and disappears, it seems as if she has backed out of her original intention.

Along the way, with the help of her neighbor and best friend Ted Nickerson (Frankie Thomas), she deals with the kidnapping of her family's doctor, a slow policeman, and an injured carrier pigeon.

Locked in a basement, Ted finds an old x-ray machine and uses it to produce radio and telephone interference, encoding it to send a call for help.