Martha Jule Beck was an American serial killer, who was part of a murderer duo, with Raymond Martinez Fernandez. Together, they were convicted of one murder and had reportedly killed nearly 17 victims between 1947 and 1949. After their trial in 1949, Martha and Raymond came to be known as "The Lonely Hearts Killers." They acquired the name since they met their victims, usually single women, through lonely hearts ads in newspapers. Many films and TV shows have been made on this case.