OPINION: Now exhibited, on a wall at the Canterbury Museum, is a painting which when seen from a distance is easily taken to be Rita Angus' 1936 landscape Cass.
Move closer, however, and one finds Rita's iconic red railway station shack liberally daubed with graffiti, while an orange road cone sits on top of a tree. In place of Angus' 1930s seated man in a hat is a 21st-century youth in a hoodie.
The work is part of a Corrupt Classics collection by a street artist known as Milton Springsteen. The power of Springsteen's art - and it deserves to be called that, having transcended beyond mere parody - lies in the way it metaphorically vandalises not only the subject of the original, familiar painting, but also our collective memory and sense of Kiwi cultural identity.
In another painting, a glum Dog from Footrot Flats sits on top of a graffiti-covered water tank; in another, Gollum from Lord of the Rings crouches by Petrus van der Velden's Otira Gorge river rapids.
The works are a very small part of the Rise street art festival currently showing at the museum, and on several large walls around central Christchurch.
Given respectability by artists such as Britain's Banksy, whose work also features in the indoor exhibition, street art is one of the hottest things in contemporary art.
Happily, there is plenty of it to see in Christchurch at present. The ruined city has given its exponents a nearly-blank canvas - although strictly speaking, of course, the point of it is that canvases aren't supposed to be used. This is art that is on the wall, but somehow also off the wall. It is colourful, it is often very clever, and it also has the sense of being rather dangerous.
The danger comes from street art's genesis in the scourge of graffiti - which makes Springsteen's re-rendering of a tag-blighted railway stop in Cass doubly challenging.
There is also plenty of graffiti and tagging around Christchurch, and most of it is as depressing as the more elevated street art is uplifting. It is hard sometimes to know where the boundary between the two might lie, and there is no doubt many a two-bit tagger who thinks he is more of an artist than he (usually he) really is.
There is also, some might argue, a risk that the acceptance of street art as a genre might also somehow encourage the permanent marker and the spray-can vandal to create more of their eyesores on unsanctioned surfaces in the city.
However, there is nothing new in this. Humans have scribbled on walls since they first used vertical structures to shelter themselves, and had a bit of charcoal from the fire to make a mark. Some sites featuring ancient art, particularly those associated with indigenous peoples, are archaeologically valuable and are sometimes considered sacred.
On a baser level, scrawled on a wall in the ash-buried Roman town of Pompeii is the nearly 2000-year old allegation "Lucilla ex corpore lucrum faciebat" - "Lucilla made money from her body".
Fast-forward to Christchurch in 2014 and the cityscape is liberally marked by colours on walls, some of it easily recognisable as art and some of it merely the spraying of young vandals with too much time on their hands, nothing interesting to convey, and certainly not enough talent.
How does one define objectively the line between the two? It is easier to tell the difference intuitively. A lot depends on the context - for example, is it sanctioned, who does the wall belong to, what is the artist trying to say, and is that person any good?
Some of the artists bringing colour and interest to the gravelled and concrete expanses of our sad and blighted city are very good indeed, and we should be grateful for that.
The Rise exhibition and festival rightly celebrates the phenomenon. Much of the work - indoors and outdoors - is large, it is certainly colourful, and if it is confronting, it is also engaging.
And for those who still don't like it, just remember, most of it won't be there forever.
- The Press