Over the Edge by Jonathan Kellerman
Brace yourself for shock - when Alex Deleware gets a phone call from a former patient, a young, troubled genius who suffered a devastating mental collapse...
when he drives through the night to save his life and winds up in a morass of murder...
when he uncovers the secret life of one of California's leading families, and is witness to an explosion of murderous passions and shattering revelations... "Over The Edge"