Julian Cope, rock star, antiquarian and author, will never be a national treasure: he's got too much attitude ever to seem that cosy. But he is a native genius, and it can only be good news that he's turned to writing novels – even if this first effort may disappoint those expecting something on a par with his wonderful 1994 autobiography, Head-On.

Cope struggles without the astonishing and compelling central character of that earlier book (which is to say, himself). This strange story of rock-star hooligans battling a Dutch cult on Sardinia and of megalithic time travel (don't ask) sometimes feels like a slog. It is also far from subtle: Cope hasn't so much turned it up to 11 as brought in a new amp that starts at 11. The result is pretty out there, even by the standards of a man who once recorded Woden – 72 minutes of weather noises and single-track synth drone. It isn't half as lovely as that album turned out to be, either.

And yet there are rewards. H is prose is occasionally superb and never less than exuberant. There are memorable images ("like uncongealing blood through a bandage, came I ever on"), fantastic rants and belly-grabbing humour, from an extravagant opening fart gag to closing explosions. The book doesn't quite come together, but it's rarely dull.