As somebody who abhors violence, I ought to feel a degree of ambivalence about Benzies, instead I feel as awestruck as an Italian peasant in the presence of Galileo. What is lost amid the brouhaha over virtual gangsters killing virtual policemen, snorting virtual cocaine and sleeping with virtual prostitutes is the incredible technological innovation and attention to detail that goes into the game. GTA IV, actually the eighth game in the franchise, takes about 60 hours to complete. (Benzies has played it about 40 times and won't play it again). Each scene is rehearsed by actors, filmed in a single take then "translated” by animators. There are about 1,000 pages of script.

"It's like making a theatre production, a few movies and an album all to fit into one package," he says. He hasn't a clue how much GTA IV has cost to make but hazards a guess at $100m. About 1,000 people have had a hand in developing it. The perfectionism Houser and Benzies demand of their teams is astonishing.

For GTA IV, time-lapse cameras were set on rooftops in New York to capture the correct intensity of the rain. Over 100,000 photographs were taken on location. In the US, a deal with Amazon lets players download any of the 150 songs they hear on the radios of the cars they steal. Liberty City has its own working version of the internet. If you blow up part of the city, you will hear about it on one of the city's half a dozen radio stations.