Philip K Dick 
Eye In The Sky 

Dreams, nightmares and realities: a classic by the author of Do Androids Dream of Electric Sheep?What begins as an ordinary laboratory visit turns into a bizarre and apocalyptic experience when a particle-light beam slices across the visitors‘ paths, plunging them into different worlds constructed from their innermost dreams and fears. As emergency works scramble to free them from the wreckage, their minds begin an incredible journey through one fantastic shared world after another.