The Spy Booth is a Banksy story that keeps unfolding with twists and turns at every corner.

First came the uplifting news story early on in the week that the Cambridge community might now be able to save their artwork from going into the hands of a London Gallery and their American investor client and keep it on the corner of Fairview and Hewlett Road.

The local businesswoman Angela De Souza’s efforts to raise funds locally through the Save The Banksy Campaign proved successful when local businessman Hekmat Kaveh rather generously came forward to purchase it.

Then there were alarming reports that the Spy Booth had been vandalised with graffiti. The mural was defaced with large scrawlings in silver and red spray paint. Passersby that saw the artwork claimed it was destroyed.

We have a curious situation here, graffiti being vandalised with more graffiti.

One version of graffiti is art, the Banksy is valued at $1.8 million US Dollars the other is not art but just graffiti or an act of criminal damage.

Locals keen to rescue the Banksy tried to remove the graffiti using toothbrushes and cloths. This public spirited act could well have done damage too. Clearly the artwork needs to be restored properly and no doubt experts will be called on to restore it properly.

Bansky used protective paint over his artwork and according to Mr Kaveh as long as the silver paint graffiti does not seep through the anti-graffiti paint it should be unharmed.

So we have art donors coming forward to save art for their community, keeping alive the debate about what is public art and we have the same story about the problems of protecting public art, a very important live issue and not just an excuse to flog street art painted on private property; art in public spaces is at risk of mindless criminal damage by those who just want to ruin it for everyone else.

Only the mysterious Banksy could get the debate going this way. His artwork often sensational and provocative, described as subversive, tackles challenging themes such as war, consumerism, capitalism and greed. This time it was surveillance by the GCHQ. This time our attention has been completely diverted away from the political message and is instead on the big question of what is street art and who owns it.

Like the thrilling pace of a spy novel, there is now a race to save the Spy Booth from lasting damage and the police are now on the look-out for the vandals. What is going to happen next? It’s a page turner.