These ersatz universes are later revealed to be solipsistic manifestations of each individual's innermost fears and prejudices, bringing the story in line with Dick's penchant for subjective realities.

While on a visit to the (fictional) Belmont Bevatron in the 1957 novel's near-future year of 1959, eight people become stuck in a series of subtly and not-so-subtly unreal worlds.

The instigating incident is a malfunction of the particle accelerator, which places all of the injured parties in states of total or partial unconsciousness.

Arthur Sylvester is an elderly political conservative and believer in an obsolete geocentric cosmology, derived from a schismatic Bábí offshoot.

Anthony Boucher lauded the novel as "nicely calculated and adroitly revealed," saying that he had "never seen [its] theme handled with greater technical dexterity or given more psychological meaning.