Shard-like fragmentation, prisms of reflected light, shafts of it exploding outward into the human reader's consciousness. How can it all cohere? And where do these meanderings lead?
There's tennis. This we know. Gerhardt Schtitt and Aubrey deLint, the clipped-consonant-named coaches at good old E.T.A. (The Enfield Tennis Academy). The kids, a school of them, from near babes to adult wannabes, names that appear and that gradually, over hundreds of pages, become personalities; John Wayne, Michael Pemulis, Teddy Schacht, Postal Weight, Ann Kittenplan, Jim Troeltsch, Ortho "The Darkness" Stice.
This is a jock novel. Sports. Sweat. Aching young bodies. Lyle the sweat-licking guru in the weight room. Locker room musings.
Oh but wait. The simmering weirdness unfolds through returned-to narratives and set pieces. Those not-quite-chapter breaks when one thread of narrative comes to a halt and the next salvo explodes from below. This is not strictly a jock book at all.
The Incandenzas start to come into view, and that view is Gothic, all blood-colored mist and dysfunction, alcohol-steeped, twisted. They are a deeply unsettling family, each individual damaged in some way, quirky, lonely, gifted but socially-challenged and, in the case of Himself, James Orin Incandenza, the besotted patriarch, avant-garde filmmaker, tennis academy founder, a suicide.
The matriarch, Avril, tall and thin, a grammarian, smokes and holds an administrative position at E.T.A which she co-founded with James O. Mother or Orin and Hal and, possibly (though hinted as not likely) Mario (whose father may actually be C.T. Tavis, Avril's half-brother, possibly explaining Mario's deformities).
Orin, the eldest son of James O. and Avril (nee Mondragon), an athlete but a failed tennis player and, as we the readers are introduced to him, a football (as in American football) punter in Arizona. Former boyfriend of, wait for it, Joelle van Dynne.
Mario, the second son who may or may not be the biological son of James O., physically deformed, a savant and, like his (maybe) father, a filmmaker. He wobbles but doesn't fall down.
Hal, the youngest, the tennis prodigy, the weed-smoking, precocious polymath who memorizes entries from the OED. An ETA standout but moody with evident addiction issues.
And there's the Gately and the Ennet House recovery facility (in close proximity to E.T.A., the Enfield Tennis Academy). Crime, addiction, recovery, Boston AA meetings, the sordid violent underside of serious addicts' lives, all of which gets explored in horrific scenes of depravity, mayhem, desperation.
This is how these two main themes connect: Tennis/ETA (and its cast of characters all with some particular dysfunction) and the Ennet House/Gately (and it's cast of characters as well - Randy Lenz, Erdedy, Joelle van Dynne, Charlotte Treat, Bruce Green, Kate Gompert, et. al.) have in common addiction & dedication (to tennis or to sobriety) and all the struggles that either entail. And those struggles unfold in dramatic and quirkily observant scenes and set pieces, in descriptions that dazzle, and in sinuous sentences that conjure the grotesque and the banal and often drape them in humor or sadness.
The third main theme that emerges does so out of the dystopian future in which the novel is set. It seems like current time (circa the 1990s) but the USA has morphed and the geopolitical structure of North America has become O.N.A.N, the Organization of North American Nations. This includes the former sovereign nation of Canada, a contingent of whose population (namely, the Quebecois) are, at the very least, disheartened by the new reality and, to the most extreme, have organized active resistance cells to attack the former-USA and endeavor to separate Quebec from the Great Concavity (a roughly 4 state-sized area of land, formerly Maine, Vermont, New Hampshire, and some of New York State that has been turned into a gigantic waste disposal area) and, by extension, from O.N.A.N.
Hence, the Assassins des Fauteuils Rollents, "...pretty much Quebec's most dreaded and rapacious anti-O.N.A.N terrorist cell." (endnote#39a pg 994).
For a deeper dive into the Quebec separatist issue, see endnote #110 beginning on page 1004 and ending on page 122 (a freaking whopper). The endnote presents, among smaller diversions, a long phone conversation between Hal and punter brother Orin, the latter of whom has inquired of his boy genius brother about the Quebec issue and what can he (Hal) tell him (Orin) about it; the ensuing transcript lays out a lot of worthwhile history to the present crisis.
Oh, and here's the tie-in twist. The Assassins des Fauteuils Rollents seek "The Entertainment" i.e. Infinite Jest, the capitvatingly deadly interlace entertainment cartridge, the great weapon (so the Separatists think) with which to wage war on O.N.A.N. Made by Himself, James Orin Incandenza, and featuring (we come to learn) Madame Psychosis herself, the veiled one, Joelle van Dyne.