As Robert Louis Stevenson established long ago in The Suicide Club, any pact like this makes a contract with the reader which cannot be voided until completed. Thus Mr. Harrison's novel, which deals with four students at a midwestern university who decide to zap themselves, will be read in the disquieting anticipation of what is to follow. In between larger questions of youthful disaffection and considerable talk on the part of their darker genius and ""intellectual commando"" Clive, one wonders just why (as will the father of Stoker, the first boy to go). Is this a sane act in an insane world? Will it prove to be ""the last great trip""? etc. etc. All of the boys are spooked by problems which they cannot altogether attach to society: Stoker, the nicest, is obsessed by his sexual desires and failures; Adler, from the Ozarks, is gauche and lonely; Pless is fatherless and his mother is given to alcoholic liaisons with just about any man including recently Stoker's father; and Clive who leads his ""actionists"" is really sick. . . . A better job than The Theologian of a few years ago, a cauterizing contemporary doomsday book which will commit the reader to determine the fate of these youngsters however capriciously ordained and reluctantly fulfilled.