All is not well at the Zoo-niverse. Animals are disappearing one by one. Things go from bad to worse when Joey Moose, one of the zookeepers, goes missing. When Mrs Gideon reports that her python is also on the missing list, Howard is determined to save the day. Howard and Vince stumble across Dixon Bainbridge's secret laboratory and the terrible truth behind his ‘experiments' comes to light.
Bollo, the eldest and most respected gorilla at the Zoo-niverse is gravely ill. Bob Fossil persuades Howard to dress in an ape suit, replacing Bollo, so that he can continue accepting sponsorship money for the gorilla. Everything's going smoothly until the Grim Reaper arrives and mistakenly takes Howard to Ape Hell instead. Vince sets off to rescue Howard and they run into trouble when they encounter the Ape of Death who is plagued with problem hair.
In an attempt to compete with daring adventurer Dixon Bainbridge, Howard and Vince set off in search of the Egg of Mantumbi - with the assistance of Gary Numan. Into the whiteness, the nothingness of the Arctic Tundra, the boys come face to face with hideous ice demon Black Frost. Luckily, Vince has befriended a polar bear.
Dixon Bainbridge, owner of the Zoo-niverse, is intent on selling to the highest bidder. There's a road being built through it and ‘if the animals won't work on it, they'll be underneath it'. Howard and Vince embark on an arduous trip deep into the Jungle Room, in search of the only man they think can help save the zoo - Howard's hero, Tommy Nookah.
Howard is hell bent on a career as a serious writer in the hope that he'll improve his chances with Mrs Gideon. However, when famous publisher Hamilton Cork arrives at the Zoo-Niverse, he decides to publish Vince's literary efforts about a pink bubblegum character called Charlie. Meanwhile, Bob Fossil has embarked on a new breeding programme for the pandas.
Vince is convinced that The Human League invented music. According to Vince, Howard's past career as a jazz trumpeter does not measure up. When Vince is offered a chance to join a new band, ‘Kraftwork Orange' with Johnny Two Hats and the Electro Girls, he's intent on leaving everything behind, including Howard.
Howard takes Vince, Naboo and Bollo on a weekend holiday to a cabin in the woods, owned by a yokel, Kodiak Jack. Naboo and Bollo, bored by the prospect of a lecture from Howard, go shopping, leaving Vince with Howard. Kodiak Jack arrives, taking a liking to Vince, and informing Howard, who is having delusions of grandeur about being a photographer, of the Yeti. Howard sets out to photograph the Yeti, leaving Vince with Kodiak Jack. While shopping, Naboo learns of the Yeti's breeding night, as Vince fends off Kodiak Jack's advances. Meanwhile, Howard is captured and brainwashed by the Yeti. Vince, Naboo, and Bollo set out to save Howard, and also end up brainwashed by the Yeti. As they are all about to be raped, they are saved by Kodiak Jack, who is then instead raped. They fled back to the cabin, pursued by the Queen Yeti, who is eventually defeated after stepping on Vince's bulging suitcase, catapulting her through the roof. Howard, Vince, Naboo, and Bollo then return to Dalston.
Howard and Vince are up late, struggling to find a new musical direction in order to get signed the next morning by Pie Face Records. To inspire them, Naboo tells them the story of Rudy van Disarzio and Spider Dijon; the Bongo Brothers, who form the band Rudi & Spider. Rudi and Spider wander the desert in search of inspiration; looking for the New Sound. After an argument, Spider leaves with the intention of drumming for Carlos Santana, becoming temporarily distracted by a town populated only by women. Rudi soon happens upon the town, meeting and bonding with an inhabitant of the town called Monkey, who tells him of a bandit called Betamax, who regularly terrorises the town. Rudi and Spider reconvene, the latter then earns himself a Door of Cuckundu by refusing tickets to Santana in Rio from Rudi, and together go to face Betamax. Spider eventually defeats him by rewinding him with his Door of Cuckundu. Rudi & Spider then showcase their newly found sound; found inside their own minds. This is of no help to Howard and Vince, whom Naboo gives Lucozade, telling them it is a magic potion to help their performance.
Vince offers Howard the chance to spend the night with two goth girls, Anthrax and Ebola, under the agreement that he dresses like a goth. It transpires Vince drunkenly bragged to the girls that he was a Warlock, stealing Naboo's book of black magic. Vince then inadvertently summons Nanatoo; the most evil demon known to man. The goth girls depart in disgust, distracting Howard and Vince from Nanatoo, who steals the book of black magic and also departs. Naboo and Bollo return, and immediately suss that Howard and Vince have summoned a demon. Naboo warns Howard and Vince of the imminence of Nanageddon, and is then summoned to the Board of Shaman who decide to remove his shaman powers, and send Saboo and Tony Harrison to retrieve the book of black magic, which neither succeed in doing; due mainly to arguing. Meanwhile, Howard and Vince retrieve the book from Nanatoo at the bingo, and flee back to the flat, pursued by Nanatoo and her army of Nanas. Naboo reverses the spell, causing Nanatoo to dissapear. The next day, a gothic Naboo and Bollo accompany the goth girls out, leaving Howard and Vince disgruntled.
Howard has an age crisis after being heckled at a gig of he and Vince's. After hearing from Bollo about the Fountain of Youth on Naboo's home planet Xooberon, Howard and Vince steal his amulet and travel there, where they wander the Desert of Nightmares and meet the Xooberon Tribe. Back at the flat, Naboo finds out about Howard and Vince stealing his amulet, and is annoyed that he has to save them. The Xooberon Tribe notice Vince has the amulet and make him their leader, and Howard his slave. Meanwhile, The Hitcher overviews these events, planning to steal the amulet for himself. Vince's status as the Chosen One is tested when a beast named Sandstorm threatens the Xooberon Tribe; Vince befriends him by gifting him with gloves which he uses to masturbate. Howard is tricked into stealing the amulet by The Hitcher, who knocks Howard out and leaves. He awakens with Vince, buried up to their necks in sand; a punishment from the Xooberon Tribe for loosing the amulet. Naboo and Bollo arrive, and accompany Vince and Howard to the Fountain of Youth, hindered by an evil tree; whom Vince summons Sandstorm to disposes of. Naboo then flushes the toilet of the Fountain of Youth, liquefying The Hitcher. The King who first gave Naboo the amulet and sent him to earth arrives and congratulates Naboo. On the way back to earth, Howard and Vince consume Youth Juice, which reverts them to babies.
After a bad gig, Howard and Vince travel to a village in Scotland called Black Lake to take a break. At the pub, they get the idea of going fishing; which Vince seems instantly proficient in. Vince soon leaves a disgruntled Howard to fish himself. Vince returns to the pub, where he learns about Old Gregg. Howard then inadvertently catches Old Gregg, who shows him his mangina, and takes him to his underwater cave. Vince phones Naboo to help him rescue Howard, which Naboo grudgingly agrees to do. Howard awakens, and has a short conversation with Old Gregg, ending in them performing a song together. While having a meal with Old Gregg, Howard learns of his possession of The Funk. While Old Gregg is preoccupied, Vince, Naboo and Bollo arrive in a submarine, and rescue Howard, who steals The Funk from Old Gregg. They use it to perform to the pub, singing a song about having the funk. They then leave, planning to bring the funk back to London. Old Gregg is shown to be riding atop their van; exposing his mangina.
Howard and Vince plan to travel to America to perform on the Pie Face Showcase. Due to Howard's fear of flying, they travel by boat, but are thrown overboard and stranded on a desert island for Vince's giving the captain a haircut whilst he slept. Howard's condition quickly deteriorates due to lack of nourishment, so they decide to eat coconuts. Howard begins keeping a journal, and Vince fashions bamboo drainpipes. Howard and Vince begin arguing, and separate to build huts: Vince's elaborate and complicated, compared to Howard's board on a stick. Howard fashions a male companion out of a coconut, calling it Milky Joe. Howard eventually builds a proper hut with the help of Milky Joe. Vince then fashions a female companion out of a coconut called Ruby. This makes Howard jealous, who fashions a wig for Milky Joe and temporarily calls her Jemima. Howard then sings a song about isolation. Vince then fashions another female companion out of a coconut called Precious Lilywhite. This agitates Howard further; he eventually persuades Vince to invite him to dinner with Precious and Ruby. Howard eventually ends up with Precious who turns out to be physically abusive. While Vince has a party on the beach, Howard accidentally kills Precious. The coconuts begin moving of their own accord; coconut police begin chasing them, they are caught and sent to coconut court, where they are found guilty of murder, and used as attractions in a coconut shie. At this point, Howard and Vince are splashed with water by a sailor, which awakens them from their rancid coconut-induced nightmare. They return home to watch the televised version of the Pie Face Showcase; headlined by Milky Joe and the Coconuts.