As soon as you enter the CCA's foyer, the promised "sensory overload" of Feral Kingdom begins, thanks to a great big mural by E*Rock and Zeloot. It is - and this is putting it as kindly as possible - not very good. Face after face is piled up in DayGlo orange and Biro blue, from freckled and fresh-faced schoolboys to gummy aliens and most points in-between. The style is probably best described as tweenage exercise- book doodle meets cack-handed graffiti, but this isn't some exploration or appropriation of juvenile folk art, it is simply poor drawing, hoping desperately to raise its game through overwhelming repetition.

Next comes a flurry of work by Zeloot and Jelle Crama. Crama is based in Antwerp, Zeloot in the Hague, and going by the selection of silkscreen posters and record sleeves tacked to a pillar here, both are designers of choice for their respective cities' cooler gig promoters and labels. Both lean heavily on 1960s, San Francisco-centred countercultural psychedelia of the sort defined by American illustrators and artists such as Rick Griffin and Stanley "Mouse" Miller, with nods to the underground comics movement.

Their adoption of the old acid drenched standards - wavy female figures, vaguely scatological imagery - is tempered by a contemporary illustration style that will doubtless mark out the first decade of the 21st century for future audiences as immediately as the groovy hippie look works as a visual shorthand for the late 1960s, complete with angled geometric lettering that, being hastily hand-drawn, is granted a rather louche looseness. The pair have obviously done their homework, fully absorbing the style of their psychedelic forbears, but the hip new twist feels forced, unlike, interestingly, some of the wigged-out noise groups their poster works promote.

On to CCA 2, which houses work by Dr Lakra, an artist and tattooist based in Xoaxaca, Mexico. He presents a huge mural, spanning the length of the gallery wall, and, like Zeloot and Jelle Crama, wears his influences on his sleeve. Cartoonists the Hernandez Bros loom large, and there are shades of Daniel Clowes, too, with a dash of Japanese Manga thrown in for good measure.

Unlike his co-exhibitors, Dr Lakra's work isn't so much informed by other artists, instead he simply apes their style. The content, meanwhile, is a witless litany of supposedly shocking schlock imagery - orgasmic porn actresses brush up against glowering super-villains, and bewigged eighteenth-century judges chow down on a cooked human corpse, overlooked by an eastern god.

Of course, this might all be underpinned by a raised eyebrow, but if Dr Lakra's joke is to present ham-fisted renderings of glib subject matter, it isn't particularly funny. Nor are his drawings, which see him take images of dolly birds and pin-up girls from dubious magazines, adding incongruous tattoos. It's a step up from idly doodling glasses and moustaches on magazine covers, I suppose, but only just.

Other works return to the tired shock tactics and derivative drawing of the wall piece, with more pin-ups, drooling African artefacts, and tattoo-style pieces combining in a yawn of hoped-for controversy. After that, the mediocre work in CCA 3 comes as a relief. Baldvin Ringstead's installation features a working Theremin surrounded by paintings, mostly religious, in which every detail has been excised except for the figure's hands. Do you see? Ringstead is matching an instrument that produces ethereal, other-worldly sounds when you wave your hands over it to images of ghostly hands suspended in the ether. Very clever.

DJ and style mag fashion photographer Matthew Stone fares better in his collaboration with performance artist The-O. On a large screen, a male figure is projected reclining on the floor naked, in a vaguely Christ-like pose, and covered with glitter. After a time, the glitter slowly rushes upward, a downfall in reverse. It's a lyrical, rather beautiful image, unencumbered by much in the way of meaning.

Lastly, there's Lolly Batty, whose sculptural work is peppered throughout the gallery. Her inclusion here is a bit of a mystery, lacking as it does the cod-psychedelic or vaguely underground sheen of the rest. Her pieces are also, surprisingly in this context, really rather good. Each is a pristinely symmetrical form with a pristine white surface, and looks like the physical manifestations of arcane mathematical formulae, which, though they are laboriously hand-crafted from polystyrene blocks, might have been made for an unknown purpose in some gleaming hi-tech factory.

That might sound like admiration for a "real" artist in the midst of disdain for designers, illustrators and tattooists, but the problem with this exhibit is not the wide net it casts across artforms, the problem is the dismal quality of most of the work. In the end, it is puzzling how the show came to be. Did no-one notice that the work being gathered together was so poor? Perhaps it is intended as a sort of insurance policy for the CCA: however flawed a future show might be, visitors will at least be able to say, "At least this isn't as bad as Feral Kingdom".

  • Feral Kingdom is at CCA, Glasgow, until November 10.