Natalie Sumner Lincoln 
The Thirteenth Letter 

The Thirteenth Letter is a thrilling detective story by Natalie Sumner Lincoln. The plot revolves around the mysterious murder of a wealthy businessman and the discovery of a series of letters that may hold the key to solving the case. As the investigation unfolds, a web of secrets and deceit is revealed, leading the detectives on a dangerous and unpredictable journey. Full of suspense and unexpected twists, ‘The Thirteenth Letter’ is a classic whodunit that will keep readers guessing until the very end.