"Every particle of the universe . . . affects every other particle, however faintly or obliquely. Everything interconnects with everything. The beating of a butterfly's wings in China can affect the course of an Atlantic hurricane. If I could interrogate this table leg in a way that made sense to me, or to the table leg, then it would provide me with the answer to any question about the universe." Or so Douglas Adams's offbeat private detective, Dirk Gently, supposes in The Long Dark Tea Time of the Soul. At another point in that same novel, Gently contends that the impossible has "integrity," while the improbable is quite commonplace. The themes of universal questions to be asked--if not answered--of the interconnectedness of all things, and the vitality of the improbable play throughout all the works of Douglas Adams with silly gusto.

Improbable is a word that quite well describes Adams's own...