Tim Walker: Why Mad Men fans are not daft

Viewing figures have fallen from 1.5m on BBC2 to 47,000 on Sky

Everyone says James Murdoch stepped down as BSkyB chairman because of phone-hacking. But his resignation also came suspiciously close on the heels of the Mad Men series premiere on Sky Atlantic. When the first episode of Mad Men's fourth series was broadcast on BBC4 in 2010, it was watched by an average audience of 355,000, rising to 1.5m with the BBC2 repeat. The recent double-bill debut of series five – its first since being poached by Sky – got just 72,000. When the next episode aired on Tuesday, viewer figures fell to 47,000.

Sky reportedly spent about £250,000 per episode to acquire Mad Men – that's more than £5 per viewer at present. A huge ad campaign was mounted to herald the show's return, and newspapers responded with acres of Mad Men-themed copy. Fair enough, you might say: the show has won 15 Golden Globes and four Emmys, after all. In the US, the Times Square billboards had the desired effect: 3.5m tuned in for the premiere, its highest stateside ratings to date. But over there, Mad Men is still on its original channel, AMC.

As Murdoch Jr will know from the Times paywall, people tend not to like forking out for things they're accustomed to getting for free. A DVD boxset costs somewhat less than a Sky subscription. And those who are so inclined can steal the show from the internet – a quick browse of some better-known download sites reveals a vigorous illicit exchange of Mad Men episodes. It's possible that a show about morally dubious 1960s ad-men appeals to people who consider themselves immune to major ad campaigns. Perhaps the sceptics would rather miss Mad Men than give Sky the satisfaction of signing them up.