Campbell, published in 1934. It tells the story of a man named Nick Carter who discovers a mysterious cipher letter that reveals a conspiracy to overthrow the government. The Cipher Letter or Nick Carter's Iron Nerve is a captivating novel written by John W. Campbell in 1934, which follows the journey of its protagonist, Nick Carter, as he uncovers a sinister plot to overthrow the government through a cryptic letter. Set in the early 20th century, the story delves into the world of espionage and political intrigue, keeping readers on the edge of their seats. The plot revolves around Nick Carter, a private investigator with an exceptional talent for solving puzzles and cracking codes, who receives a mysterious letter containing a cryptic message that sets him on a dangerous mission to uncover the truth behind the letter. As he delves deeper into the mystery, he finds himself entangled in a web of deceit and conspiracy that threatens to destroy the very fabric of society. With the help of his trusty sidekick, a brilliant scientist named Dr. Percy Harkness, Nick must use his skills and knowledge to decipher the code and bring the perpetrators to justice before it's too late.

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