‘Y'all don't know, but Poe know!’, Sun Ra reportedly told musicians at his rehearsals (Szwed Reference Szwed1997, p. 130). When it comes to improvised music before 1970, one thing is clear: Toop knows. And now, thankfully, we know too. His book on this topic, Into the Maelstrom, already gives a sense of its richness and depth of insight by its title alone, in the way it omits the would-be first word (‘Descent’). The title is borrowed from that of improviser Lennie Tristano's 1953 Edgar Allan Poe-inspired multi-tracking experiment, which itself drops the leading article from Poe's 1841 original, ‘A Descent Into the Maelstrom’. This progressive elision of title words is arguably not just about language economy, but semantics: while Tristano's subtle tweak lends a sense of real-time urgency to the implied act of descending, Toop's further contraction speaks to his artfully presented account – less of a descent and more of a headlong hurtling into the abounding stream of grist he mills for our benefit.

Astoundingly, there is no chaff to be found, despite the complex task of producing a meaningful, coherent blend of names, dates, places, facts, anecdotes, interviews, references, interpretations, narration and methodological clarification. As an example of Toop's unique approach, he cites a 1948 radio listener report invoking Poe to connect the Tristano recording referenced above to an early Pierre Schaeffer broadcast (p. 100). Toop here is at times more detached and analytical, assuming the role of academic ethnographer, historian, theorist and discographer. At other times, his own invaluable perspective is allowed to come through more strongly, as an active, influential musician often physically in the midst of a significant portion of the music-making, conversations and events depicted. Yet the author interweaves himself into the synchrony in such a way that he never steals focus, but instead nimbly absorbs the reader into the ever-unfurling tapestry.

While some may find the ‘feel’ of the text to be akin to Hunter S. Thompson's gonzo journalism, it is perhaps closer to Guy Debord's notion of psycho-geography, in that the environments, events and personae are as effectively portrayed and analysed as the interactions among them. (To give a sense of the book's unparalleled breadth within the still-nascent field of improvisation studies: Debord himself even makes a cameo appearance on the heels of a fascinating fragment about fellow Situationist Asger Jorn's musical improvisation experiments with visual artist and Ellington-fan Jean Dubuffet; see pp. 162–164.) More conservatively, one might describe the book as a social anthropology of a community, in which no single individual or group is held up as chief protagonist. Indeed, even as the cities of London and New York reveal themselves as undeniable ‘stars’, they are (along with their most famous inhabitants) denied the usual overshadowing star treatment in favour of a careful, revelatory balancing act.

Fortuitous contingencies – as when a meeting of two musicians at a film screening leads to a fruitful, high-impact collaboration (p. 261), or when a musician's apprenticeship at an art exhibition radically alters his aesthetic trajectory (p. 295) – are anchored in social and material context, throwing otherwise hidden significance into relief (the aforementioned film screening took place after the first decade of electronic music in film and television scores; the art exhibition was responsive to the then-escalating Vietnam War). Meanwhile, the context itself is rendered as a persistent flux of makings and unmakings, gatherings and dispersals, on both a microcosmic and a (literally) global scale. Toop expertly guides the reader through such ephemera across an expansive scene in which, from one performance to the next, ‘each group could sound radically different according to mood, room acoustics, personnel on any given day, instrumentation, recording engineer and equipment, the disposition of the audience and the temper of the times’ (p. 191). Ever adroit in confronting messy reality, Toop continuously resists the easy slide into reification that would be inevitable in less capable hands.

In each chapter, connections to jazz, composed music, film, painting, literature, pop culture and more permeate tales of group formations, club foundings, rehearsals, live performances, recording sessions and animated conversations, across the UK and European continent, the USA and Asia, and occasionally in Africa, the USSR and beyond. The reader is invited to bear witness from multiple perspectives at once – not a fly on the wall, but one in perpetual flight – which produces a palpable cumulative effect on a linear read-through. At the same time, the chapters are divided into short, easily digestible sections, seemingly readable in any order, which lends itself to reading on the go or in other circumstances with frequent interruption.

Those accustomed to a traditional presentation style may search in vain for a conventional backbone to what is, in essence, a portable archive. However, the apparent lack of structure is by no means due to a lack of effort, as if shoeboxes full of material were mindlessly emptied into a sack. Rather, by design, the clearly painstakingly excavated contents that comprise the archive are presented as a curated exhibition. This authorial strategy allows one to wander through freely, along a designated path, or as haphazardly as one desires, attending to the deeply considered placards, or fixating only on the curios themselves. As any good curator would facilitate, Toop brings each element to life, preserving its magnetic pull, and ultimately mapping out a constellation that includes even the faintest shimmers in the distance.

In short, there is a wide range of substantive material here for both scholars and fans of the music. While encyclopaedic in scope, those looking for a reference work in the form of a dictionary-style compendium will be disappointed, although the book does feature a comprehensive index of names (not topics), an abbreviated discography and detailed bibliographic notes. Equally, one should not expect a latent oversimplified lesson plan on the history of contemporary improvisation à la ‘Beethoven, Bach, Brahms’, although the book could easily serve in advanced pedagogical settings. If one accomplishment of the work must be singled out, it is that it assumes no foreknowledge of improvised music, and yet it would enrich the understanding of anyone who considers themselves an expert on the subject.