The Brentford Chainstore Massacre by Robert Rankin

From Amazon.com:

THE FIFTH NOVEL IN THE NOW LEGENDARY BRENTFORD TRILOGY
WITH A SPECIAL ADDED BONUS

This book is the fifth in the now legendary Brentford Trilogy, a work of "deformed brilliance" (Observer) and to make it just that little more interesting, Robert Rankin has added an extra something. Within the cover art for this title is encoded a secret message. Can you crack the code? And decipher the message? If you can there is a prize to be won. A complete set of signed and numbered prints of the black and white cover art from the twenty-three Far Fetched Books Robert Rankin ebook collection. (Check them all out on Amazon). A unique prize. Go on, go for it.
When you think you have cracked the code message Robert on his Facebook page.
Good luck

Doctor Stephen Malone is cloning Jesus Christ from the blood on the Turin Shroud. And not just a single Jesus, he's cloning six, so that each of the world's major religions can have one for themselves. It has to be the very worst idea of the twentieth century. And what is more, he is doing it in Brentford!
Mind you, the plucky Brentonians do have a lot of other things on their minds at the moment. Such as putting their plans to hold the Millennial celebrations two years early into action. It is something to do with a tradition, or an old charter, or something.
John Omally and Jim Pooley are once more in the thick of it. As are Norman the corner-shop keeper, Professor Slocombe, Neville the part time barman and all the stars of books previous. And they are all going to be drawn into the adventure of a lifetime.

This book is part of the "Brentford" series.
Here are some other books from this series: