The Hour, Series 2 Finale, BBC Two

When the first series of The Hour aired last year, there was a lot of excitable talk about how it was the "British Mad Men". Having sat through series two, I've concluded that in fact it's the British version of Pan Am, that bizarrely idiotic airline series where all the air hostesses were covert operatives for the CIA, and visits to exotic international locations were achieved using plywood props and big photographs of famous landmarks.

Despite its superficial attention to 1950s detail (suits, hats, frocks, cars), the more The Hour tries to feel authentic, the less convincing it becomes. Surely they could have found a way not to make the BBC's Lime Grove studios look like a derelict Odeon cinema? Writer/creator Abi Morgan has repeatedly tumbled into the elephant trap of reheating famous scandals and media sensations from the era and bolting them together into what is supposed to be the plot, with a particular obsession for Soho vice rings and the nuclear threat. Both of these implausibly collided under the roof of sleazy Soho clubland entrepreneur Raphael Cilenti (Vincent Riotta, pictured below).

Any night of the week, it seemed, you could stroll into Cilenti's El Paradis club and find the entire staff of BBC and ITV television, the Cabinet, and most of Scotland Yard's senior police officers. So irresistibly alluring were Cilenti's girls, wiggling in their basques and suspenders to a soundtrack of feeble pseudo-jazz, that wealthy and powerful men formed orderly queues to tell them all their dirtiest, darkest secrets and to be covertly photographed while having a good grope. Cilenti, rather offensively played as a greasy cartoon wop, smirks and gurns malevolently, and if any of his underlings step out of line they end up dead. Meanwhile he's been overseeing a vast racket in which NATO's nuclear strategy will bring big bucks to a company owned by his mate, a Mr Tufnell.

The idea that a primitive BBC television news programme reliant on a solitary reporter and with no outside broadcast teams would expose this seething morass of corruption in high places and bring down the government was never remotely feasible. In the wake of what we've learned about the BBC's investigative news operations in the last few weeks, it's absolutely hilarious. Peter Capaldi, playing the perpetually glum head of news Randall Brown, warned his team, apparently without irony: "It's risky so let's get our facts straight" (rather an understatement, given the sackings, lawsuits and arrests that would follow mistaken outings of assorted ministers and top coppers). The line was almost as good as the one he uttered after the death of vice girl Rosa, murdered when she threatend to expose Cilenti to The Hour: "We have rattled Mr Cilenti's cage!" Bravo, The Hour!

In this wonderland of unlikelihood, the cast inevitably faced an uphill battle. Bel Rowley (Romola Garai, pictured left), producer of The Hour, vacillated erratically between doe-eyed love interest and neurotic TV executive, never fully engaged in either. Ben Whishaw's Freddie Lyon was supposed to be a beacon of idealistic truth-telling and fact-uncovering, but while the role called for him to go snooping around like some hard-bitten gumshoe, he more nearly resembled an irritating know-it-all wonk from some nebulous think-tank.

It was typical of Morgan's anachronistic tone. Her characters are so fond of delivering lectures about immigration, racism, the evils of nuclear proliferation, journalistic integrity, corrupt politicians (Tory of course) and the outrageousness of the homosexuality laws that the script might have been pasted together from back issues of the New Statesman.

Still, just because it's the silliest show on television, that doesn't mean that series three, four and five aren't already in preparation. I just hope they don't get rid of Anna Chancellor's Lix Storm - though maybe they could find her a name that doesn't sound like it came from some bondage website - because she's the sole cast member who looks as if she's in the right place at the right time.