Physicist/expositor Davies (The Edge of Infinity, God and the New Physics) projects a personal dream of physicists' glory--i.e., some day soon physics will achieve that grand unification theory that has the inglorious acronym, ""GUT."" The unification may be accomplished, further, through the operation of a superforce that would embody the known and hypothesized ""messenger"" particles--glutons, photons, gravitrons, and the like. These messengers orchestrate the interactions in force fields that bind protons and neutrons in the atomic nucleus (the strong force); they explain radioactive decay and the existence of neutrinos (the weak force) and account for the more familiar electromagnetic force binding electrons to atomic nuclei; and, most familiar of all, they govern the force of gravity. The theoretical prediction of messenger particles (Z and W) led to Nobel prizes for Abdul Salam, Steven Weinberg, and Sheldon Glashow even before experiments conducted at CERN in Geneva confirmed their mathematics. Davies, ever ebullient and optimistic, feels that the day is not far when similar bold mathematical formulations--such as the superforce--will similarly see experimental confirmation. In the meantime there remains more than one theory, conundrum, pitfall; more than one way of dealing with mathematical problems that arise from subtracting multiple infinities from equations (amplifying the discussion in John Boslough's book on Stephen Hawking, above). Davies deserves praise for this formidable excursion into the excitements of present-day particle physics for the lay reader. He builds his story deftly from the historical and common-sense approaches to the paradoxical worlds of uncertainty, virtual particles, and non-empty vacuums. He is particularly zealous in explaining gauge theories and the various symmetries whose preservations lead to the mathematical conceptualization of space as no less than 11-dimensional. Not all is proven, however; not all may even be on the right track. But for patient readers there are enough insights, enough offhanded explanations of everyday phenomena, and enough celebration of the beauty-symmetry-elegance-truth arguments to reward perseverance.