As another US general becomes embroiled in the scandal involving former CIA director David Petraeus, Felicity Spector sifts through the details of a story that gets more unbelievable by the day.

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If this was the plot of the latest James Bond film, you might forgive it for stretching the truth.

In just a few hours the revelations about the former CIA director, General David Petraeus, and his lover Paula Broadwell have widened to include another four-star general, a shirtless FBI agent, the Washington super-lawyer who represented Bill Clinton and John Edwards, and dark mutterings about there being "more to this than meets the eye."

More to this? The mind boggles. This is already the kind of story which comes peppered with the word "allegedly" and the kind of salacious details not normally seen in august publications like the Wall Street Journal.

The new centre of the saga is Jill Kelley, an unpaid "social liaison" to a US base in Tampa, Florida. Kelley and her surgeon husband were known to be close friends of General Petraeus and his wife Holly, inviting them to some of the high-profile social gatherings they held at their £1m luxury home.

It was Kelley who first alerted the FBI, after she allegedly received harassing emails. She contacted an agent who she knew - who was subsequently removed from the investigation, according to the Wall Street Journal, after he became too obsessed with the case.

Shirtless agent

He is the agent who reportedly sent Kelley a shirtless picture of himself. Not only that. He was apparently concerned that the investigation might be swept under the carpet, so he contacted a Republican congressman with details.

Those details were passed to house majority leader Eric Cantor at the end of October, but he did not pursue the matter immediately, as there was no proof that it was true. This, remember, was before the presidential election and long before the senate intelligence committee, let alone the White House, knew anything about it.

Not content with embroiling one top US army figure into the mix, now General John Allen, head of US forces in Afghanistan, has been accused of sending up to 30,000 documents, many of them potentially inappropriate emails, to Kelley. Yes, you got that right.: 30,000.

Allen took over from Petraeus as commander of US operations in Afghanistan in 2011. He was due to be appointed as Nato's supreme allied commander in Europe, but all that has now been put on hold. Stars and Stripes magazine reports that he says he has done nothing wrong.

Well-known trick

In the meantime the FBI has been seen raiding Paula Broadwell's house overnight, carrying away a number of boxes. Friends of General Petraeus told the Associated Press that he was shocked to hear about the allegedly threatening emails sent to Kelley, and denied that he had anything to do with the sensitive military information alleged to have been found on Broadwell's computer.

The emerging details get more and more bizarre. Petraeus and Broadwell apparently communicated with each other using a rather well-known trick which they naively thought would make their emails impossible to trace: saving them as drafts in their shared inbox.

There are still mutterings about political conspiracies and cover-ups. Former labour secretary Robert Reich is among those demanding answers.

No-one has committed any crimes here. But there may well be many more questions to come. Paula Broadwell's father, Paul Krantz, told the New York Daily News he believed this was just the tip of the iceberg: "There is a lot more that is going to come out... You wait and see. There's a lot more here than meets the eye."

President Obama, back at work today after the Veterans Day holiday, is due to hold talks with congressional leaders on the vastly more important, but far less entertaining "fiscal cliff" which threatens to plunge the US economy back into recession if it is left unresolved.

But you can bet he will be asked about the Petraeus scandal - what he knew, and when, and the kind of culture at the top of America's armed forces which led to all this in the first place. Headlines about the debt crisis are not nearly as compelling as this.

Felicity Spector writes about US politics for Channel 4 News

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