Wesley Shermantine, One of the Speed Freak Killers, Dies at 60

Wesley Shermantine, who died in prison at age 60 on September 17, 2026, was one half of California's notorious "Speed Freak Killers." The name came from the methamphetamine use that accompanied the duo's murders in the 1980s and 1990s.

Shermantine and childhood friend Loren Herzog, the other half of the murderous pair, were arrested in March 1999, though only Shermantine would spend the rest of his life in prison.

Authorities considered Shermantine and Herzog possible murderers long before they were arrested. Cyndi Vanderheiden, 25, had been seen with the two before she disappeared in November 1998. Finding her blood in Shermantine's car provided a key piece of evidence.

In addition, new DNA analysis proved that blood from Chevelle "Chevy" Wheeler, a 16-year-old who disappeared in October 1985, was in a cabin Shermantine owned. He was charged with her death. Tire tracks where Paul Cavanaugh, 31, and Howard King, 35, were shot in 1984 were found to match the truck Shermantine drove at the time, and he was tried for killing them as well.

Shermantine tried to pin the blame on Herzog, but on February 14, 2001, a jury found him guilty of all four murders. He rejected a deal to escape the death penalty in exchange for the location of Vanderheiden and Wheeler's remains, wanting money instead.

Shermantine was sentenced to death in May 2001, though his capital punishment would never be carried out.

Herzog told police Shermantine was the only one of the two who carried out the killings, but in October 2001, he was convicted of Vanderheiden, Cavanaugh and King's murders. He was also found guilty of being an accessory to 41-year-old Henry Howell's robbery and murder. Herzog received a 78-year sentence.

In 2004, Herzog's convictions were overturned when a court found that his confession was coerced. Because his confession could no longer be used against him, prosecutors agreed to a deal: Herzog pleaded guilty to manslaughter for Vanderheiden's death and three counts of being an accessory to murder in the Cavanaugh, King and Howell killings. He got a 14-year sentence.

In September 2010, Herzog was paroled to a trailer on the grounds of a state prison.

By 2011, Shermantine, then on Death Row, was talking to a bounty hunter about his crimes. Shermantine agreed to a deal that promised him $33,000—$18,000 of which would go to victim restitution—if he helped locate remains.

In January 2012, the bounty hunter called Herzog to say Shermantine was mapping out burial sites. Herzog died by suicide shortly afterward.

Authorities discovered human remains at three different sites. An old well that Shermantine referred to as "Herzog's boneyard" held more than 1,000 bone fragments. Vanderheiden and Wheeler were identified from these sites, as were Kimberly Billy, a 19-year-old who vanished in 1984, and Joann Hobson, 16, who went missing in 1985. The remains of another female victim and a fetus were also recovered, but their identities are still a mystery.

In February 2012, Shermantine told a reporter he regretted burying victims but hadn't killed them. He admitted in a May 2012 interview that he'd played an "active role" in the murders but continued to call Herzog the killer.

Shermantine had stopped cooperating by 2013 and the search ceased. He never faced additional charges.

In his interrogation, Herzog said Shermantine had admitted to killing 24 people. During Shermantine's trial, the prosecutor called him a suspect in 20 killings.

A former prisoner came forward after Herzog's death to say he'd confessed to committing 112 murders with Shermantine. In 2012, Shermantine told a news station there'd been 72 victims, though he named Herzog and an unknown third man as the killers.

Investigators also suspected Shermantine and Herzog of murders outside of California.