Following his fine Project Pope, Simak delivers another low-key charmer--this time involving alternate worlds and human futures. English professor Edward Lansing, after consulting a talking slot machine, finds himself on an alternate Earth together with a motley collection of characters from other alternate worlds and times: a puritanical Parson, an officious Brigadier, dreamy poet Sandra, engineer Mary, robot caretaker Jurgens--and a mysterious quartet of card-playing aliens who ignore the Earthlings entirely. The world features an inn and a road and not much else; with little choice but to follow the road, the party stumbles across a number of puzzling objects: an immense but unapproachable blue cube, an abandoned crumbling city, a set of doorways to alternate worlds, a space-time transport device, a curtain of Chaos, a singing obelisk. Each object has its unseen dangers, and the casualties mount up--until, in an appropriate but not altogether surprising ending, it's up to Lansing and Mary to solve the riddle of the blue cube, enter, and demand some explanations from the card-playing aliens within. Simak's prose is better than ever, clean and supple and occasionally brilliant; and his alien conundrums are appealing and persuasive.