On March 26, 1997, Sheriff's Deputies responded to an anonymous welfare check call at a mansion in Rancho Santa Fe. 

When deputies made their way inside, they made a shocking discovery.   

In all, 39 members of the "Heaven's Gate" cult were found dead.  An investigation by the San Diego County Sheriff's Department determined they all took part in a mass suicide that took place over the course of several days. 

Media from all around the world descended on Rancho Santa Fe to cover the story. 

The Heaven's Gate case remains the largest mass suicide in U.S. history.