Ubik

A classic science fiction tale of artifical worlds by one of the great American writers of the 20th century Glen Runciter is dead. Or is he? Someone died in the explosion orchestrated by his business rivals, but even as his funeral is scheduled, his mourning employees are receiving bewildering messages from their boss. And the world around them is warping and regressing in ways which suggest that their own time is running out. If it hasn't already.