Leonard Lake and Charles Ng were a pair of serial killers, rapists, and abductors believed to be responsible for as many as twenty-five murders.

Lake was born in San Francisco, California, in 1945. When he was young, his parents separated and he and his siblings were sent to live with their grandparents. At an early age, he began taking nude photos of his sisters; this became the start of his obsession with pornography. He also enjoyed killing mice by dissolving them in chemicals. In 1965, aged 19, he enlisted in the U.S. Marine Corps and did service in Vietnam during the war as a radar operator. During his first tour, he was hospitalized for ""exhibiting incipient psychotic reactions"" but was returned to duty after a short time. In 1971, he was given a medical discharge, having been diagnosed with schizoid personality disorder. He moved to San Jose, California and attended the San Jose University, but dropped out after only one semester and joined a hippie commune. Around this time, Lake became obsessed with the idea of a global nuclear war and developed a kind of survivalist paranoia and with it an obsession with guns. He met a woman named Claralyn Balazs, a 25-year-old teacher's aide whom he nicknamed ""Cricket"", in 1977 and married her in 1981 and moved in with her. Shortly afterward, he met Charles Ng. Lake would star in S&M- and bondage-related amateur porn movies and also made Balazs take part in them. He had been married to another woman before her in 1975 while he was serving in Vietnam. Like Balazs, she left him when she could no longer put up with his sexual deviance.

Ng was born in Hong Kong in 1960. His father, a business executive, was strict and disciplined him through physical abuse. From an early age, he displayed an obsession with martial arts and fire-setting and also had a lifelong addiction to stealing. At the age of 15, he was arrested for shoplifting and sent by his father to a private boarding school in England in an attempt to change him, from which he was expelled for stealing from his fellow students and sent back to Hong Kong. In adulthood, he moved to the United States and enrolled in the Notre Dame de Namur University in Belmont, California, but dropped out after his first semester. In October of 1979, he was arrested in relation to a hit and run accident and forced to pay for damages. In 1980, he lied about his nationality and joined the USMC. He was dishonorably discharged after less than a year for stealing automatic weapons worth $11,000 from the gun storage of the Marine Corps' base in Kaneohe Bay, Hawaii. Though sentenced to 14 years, he escaped and made his way to California, where he met Lake. Though some sources claim that they met when Lake posted an ad in a survivalist magazine, this cannot be confirmed. After meeting Lake, he moved into his ranch.