The scene is the strife-ridden ship Yukoku, part of a mission against a hostile race in the region of Altair. Almost at once, Tamura, the ship's ruthless Japanese commander, stumbles onto some appalling truths about the intentions of RUllkotter, the twisted genius who designed the mission's computers (""Machine Intelligences""). Tamura and the squabbling crew struggle to abort the MI sequences that have been designed to ""assimilate"" them into transistorized analogues of themselves--all but one near-psychotic crew member who proves mysteriously immune. But further shocks await the MI itself at Altair III, the ""catchworld"" which has akeady lured six civilizations into its clutches, and where a still more dreadful creation of Riillkotter has preceded the MI. If everything lived up to the ingenuity of this design, Catchworld would be simply first-rate. As it is, the frequent carelessness of the writing and the olla-podrida clutter of the denouement are major defects. Messy but promising.