The second installment in Alan Moore's Long London series, set primarily in 1958–1959, follows Dennis Knuckleyard, a struggling 27-year-old freelance writer in London's East End, as he is drawn back into the Great When, a hidden, timeless, symbolic version of London that exists in parallel to the ordinary city. In the previous novel,
The Great When, a teenage Dennis stumbled into this shimmering metropolis, where all eras coexist, streets are paved with gold, and giant symbolic figures called Arcana embody the city's deepest forces. He barely survived, killing a man named Clive Amery during his previous ordeal, a secret he has buried along with every memory of his time there.
A prologue spanning several decades establishes the supernatural framework. In 1913, a shire horse falls into a pit at Arsenal's stadium site and dies; years later, a glowing Arcanum called Slenderhorse whispers its skeleton back to life. In 1956, the dying artist and magician Austin Osman Spare senses that something has gone wrong in the Great When. In 1957, Joe Meek, a young, gay, amphetamine-fueled record producer in Notting Hill, obtains an old iron key from Dennis at a party and uses it in a séance, where it turns by itself inside a tied-shut Bible. The key is an artifact from the Great When, a dangerous leak between the two cities called a "breach."
Dennis's ordinary life shatters in October 1958 when Meek bursts into his flat, interrupting his date with Denise, a receptionist at
Reveille magazine. Meek accuses Dennis of giving him something that has caused terrible trouble: bizarre séance results, a tarot prediction of Buddy Holly's death, recurring nightmares, and a sighting during the 1958 Notting Hill race riots of the Inferred Saracen, a supernatural eight-foot Arcanum. Dennis realizes the key's presence may have influenced the riots and offers to take it back, but Meek refuses, having wired it into his recording equipment. Denise, misunderstanding the situation, leaves permanently.
Dennis resolves to do nothing. Months pass. Then, in January 1959, he is chloroformed in his own flat and confronted by Coffin Ada Benson, his ancient former landlady from a Shoreditch bookshop, and her mute enforcer, Commotion Venables. Ada reveals that Grace Shilling, a young woman Dennis knew from his earlier ordeal, has been recruited in his place and has already entered the Great When. Dennis insists on going after her.
Commotion drives them to the French, a Soho coffee shop, where Ironfoot Jack Neave, the self-crowned "King of the Bohemians" and an old ally familiar with the Great When's workings, lies dying of cancer. Jack explains that the Great When's City Heads, a council of literal severed heads preserved in jars, need a human investigator. Grace entered two hours ago, escorted by Maurice Calendar, a shape-shifting intermediary between the two Londons.
Dennis enters the Great When through a portal in Bride Lane. He encounters Slenderhorse, who lends him an Oxtercross, a map of the hidden city, and warns that her key must be returned. He catches up with Grace and Maurice, who has "pupated" into a scruffy beatnik. At the Crown and Dolphin pub, the ruling triumvirate of City Heads, comprising Oliver Cromwell, John Williams, and Emanuel Swedenborg, reveals that too many breaches have occurred. Swedenborg foresees the Great When's ruin by the century's end. Worse, Button Dainty, one of the Great When's two enforcers, a tiny, lethally dangerous creature whose face constantly rearranges itself, has gone missing. The heads task Grace and Dennis with finding him.
At the Pallors of Worstminster, the Great When's version of Westminster, they observe the House of Uncommons, a warped counterpart of the House of Commons, where Broadstair the Prime Monster is lobbied by the Barebones, skull-faced property developers who plan a covert expedition to ordinary London's Cripplegate. The investigation then proceeds in ordinary London. Through David Litvinoff, a brilliant East End hustler, Grace and Dennis pose as ghost hunters and visit the slumlord Peter Rachman but learn nothing. On January 29th, a smog engineered by Broadstair covers the Barebones' activities at Cripplegate, where Grace and Dennis observe them surveying the ground beneath the spectral arch of the Roman fort gate.
On February 3rd, they enter the Great When through Notting Hill and witness the climactic union of two colossal Arcana, the Inferred Saracen and the Beauty of Riots, whose coupling resolves months of supernatural confrontation in the Great When's counterpart of Notting Hill. Returning to ordinary London, Grace and Dennis begin a passionate relationship. The next morning, Meek arrives with devastating news: Buddy Holly has died in a plane crash on February 3rd, exactly as the séance predicted, a year late. The "dirty shirts" nightmare was prophetic too: The performers chartered the fatal plane because their stage clothes needed laundering.
The investigation stalls through spring. Rachman's suspicions from the earlier visit lead to a violent confrontation at the French café, and the group relocates. Dennis's old friend Tolerable John McAllister suggests visiting the Great When's literal Hell, since Button Dainty was last investigating the source of Enoch Soames's breached poetry collection
Fungoids. In late April, Dennis descends alone to the Good Samaritan pub in Whitechapel, Hell's "convivial reception area." The devil identifies the person who smuggled
Fungoids into the mortal world as Prince Monolulu, a racing tipster. As Dennis flees, the devil remarks within earshot: "He'll be back. He's murdered somebody" (223).
Monolulu confesses that Slenderhorse manipulated him decades ago into retrieving
Fungoids from Hell, then intercepted Button Dainty to prevent the enforcer from punishing Monolulu. Meanwhile, interludes reveal that Button Dainty has been appearing as a hallucination to Ronnie Kray, one half of the infamous Kray twins, goading the gangster toward territorial expansion.
After months of failed attempts to recover the key, Dennis takes Meek into the Great When to return it. Slenderhorse admits she orchestrated events for amusement and reveals that Button Dainty can be found in London's criminal underworld. Maurice Calendar announces he must pupate again and tearfully departs. In late September, Litvinoff arranges for Grace and Dennis to observe Ronnie Kray at the Regal Billiard Hall in Mile End, where they see Button Dainty perched on the gangster's lap. Dainty spots them and pursues, first at inhuman speed, then as an invisible poltergeist creating a trail of destruction through the streets.
A cab takes them to the ruins of Cripplegate. Button Dainty materializes and threatens to kill them. Dennis stalls with disinformation until the Cripple Gate manifests and Charming Peter, the London Cat and the Great When's other enforcer, emerges. Peter turns Dainty inside out and warns Dennis: "You smell of secrets and disaster" (293).
That same night, Gog Blincoe, a Great When entity and towering market trader made entirely of wood who has been attending to the dying Ironfoot, carries Jack through the carnivorous streets of Soho Entire, the Great When's counterpart of Soho, to the Crown and Dolphin, where Jack delivers a profanity-laden speech shaming Cromwell's faction into abandoning their planned war on Worstminster. Jack dies on the journey back to ordinary London.
In the aftermath, Maurice Calendar reemerges as a Mod on a scooter, signaling a new cultural era. Dennis watches Grace perform a stunning marionette routine at Paul Raymond's Revue Bar, her art transcending its setting. Meek drives through Holloway Road, inspired by sounds from the Great When, spotting what will become his famous studio and carrying a secret book Slenderhorse gave him. Dennis lies awake accepting the Great When's permanent claim on him: "He was starting to get the hang of this" (313). An epilogue set in November 1999 shows an elderly Dennis on Charing Cross Road, where a young homeless man recognizes him and calls out, "Dennis?" (319). Dennis flees, confirming that the uncanny has pursued him across four decades.