Richard, a moderately successful composer, and his old university pal John Sinclair, a physicist, go for a camping holiday in the Scottish Highlands during which John inexplicably vanishes for thirteen hours, returning both mystified and very subtly altered. He has to cut the vacation short because called back to London: a space experiment is returning anomalous results -- alarmingly anomalous, in fact. The two men fly out to California and thence to Hawaii; while they're in Hawaii, suddenly communications with the mainland go dead. As they and their American friends mount expeditions to explore what's going on in the rest of the world, it's Sinclair who first pulls everything together. Some entity, never identified (beyond a deduction on p198 that it's some form of higher consciousness, as ineffably far above us as we are above a nest of ants) and for reasons unknown, has made of the inner Solar System a sort of gigantic time machine, and the earth, passing through its temporal beam, has been differentially jolted into different eras of the past and future: while the UK and Hawaii (and presumably other regions) are still in 1966, Western Europe is still -- or once more -- being ravaged by the Great War and Greece is enjoying the glories and privations of 425BC. Most alarmingly, Russia and much of Asia are covered by a hard, impossibly smooth vitreous plain, which Sinclair deduces is an indication that they've been cast into the very far future, where the heat of a swollen sun has boiled away the atmosphere and melted and fused the earth's surface. (Here Hoyle's imagination runs into consistency problems: our heroes visit these regions and notice neither a redly bloated sun in the sky nor a lack of atmosphere. Perhaps the notion is that the air from elsewhere around the globe has rushed in to fill the vacuum, but this would lead us immediately to start considering other problematic "leakages" between the earth's different, coexisting temporal zones.)
Richard is much drawn to Periclean Greece, and joins a small expedition that ventures there to live among the Athenian people. The expedition is concerned not to inflict too severe a culture shock upon the Greeks, and thus introduce themselves there as "strangers from afar" and abjure most of the trappings of modern civilization -- although Richard does take with him his piano. Because of the situation the novel portrays, there aren't any of the considerations to be taken into account concerning the alteration of the past; the visitors thus strive to put an end to the Athenians' war with Sparta, a war which, they know, will if left unchecked bring both cities to their knees and leave the civilization of ancient Greece ripe for barbarian conquest. They succeed in this through help given from an unexpected source: the Delphic Oracle.
Richard accepts a challenge from a beautiful priestess of Apollo: a musical contest between himself and her god. A huge audience gathers to watch Richard perform on his piano; the god, discreetly, performs out of sight. As they trade party pieces, it becomes evident to Richard that Apollo -- or whoever is invisibly playing -- has created music quite unlike anything he's heard before, and certainly far more sophisticated than the offerings he's encountered so far during his Greek sojourn. At the end of the contest, he and the priestess agree that the only fair outcome is to declare the contest a draw. They celebrate this judgment in a manner not usually associated with the Supreme Court (at least, we assume not) and then Richard falls into a deep and dreamless sleep . . .
. . . to awaken in the distant future. Sinclair has been brought here, too, and explains that, as he'd expected, at least one of the far-future societies brought by the "time machine" into coexistence with 1966 Britain has been concealing its presence from the rest of the mixed-era planet. Richard's "priestess", Melea, was in fact an explorer from the future who'd come to investigate his anachronistic presence in 425BC Greece; her pal Neria was meanwhile subverting the Delphic Oracle into a fit of pacifism. Melea introduces Richard to various far-future technological wonders, such as CDs that are conveniently only the size of dustbin lids. More somberly, the 20th-century visitors are shown a sort of movie of the history of the human species between their own time and the sparsely populated distant future of Melea and Neria. They learn that, not once but countless times over the past millions of years, humanity has allowed itself to expand uncontrollably until a moment of precipitate and horrific collapse, with inordinate suffering; in the wake of each catastrophe the small surviving relic has promised itself that this time they will learn from the past and it will be different, and yet of course . . . The question Melea and her society want the two Englishmen to answer is, in effect: Is it worth it? Of course, there isn't a real answer to that.
The tale is told in the same sort of Buchanesque mode that Hoyle adopted for Ossian's Ride; the contrast between the bluffness of style and Richard's supposed sensitivity as a musician works surprisingly well, and it adapts well too to the occasional didactic passage. These latter are always welcome components of Hoyle's novels; here he gives us a few pages (pp75-7) of happy speculations about the nature of time and consciousness. One oddity is that the events of the first few pages seemed to me wildly reminiscent, albeit it in a different order, of parts of Ian McEwan's 1998 novel Amsterdam; I wonder if McEwan read October the First is Too Late decades ago (as I did) and (like me) forgot most of the incidental content, only for it to come bubbling up from his subconscious when he was writing Amsterdam? There's quite obviously no question of plagiarism, deliberate or unconscious; it's just an oddly similar pair of juxtapositions of events. It's certainly pleasing to think that something of Sir Fred's hobby might still be swimming in literature's river.