Annie Machon, former MI5 agent, is the image of glamour and guts. Her blonde hair, of the bombshell variety, frames a face that, far from being that of the reserved and stealthy spook, exudes energy, enthusiasm, and openness.

Unlike her former partner, the whistleblower David Shayler, Machon seems to have emerged relatively unscathed from the years immediately following the couple’s attempts to reveal serious MI5 blunders in 1996.

Now working as a self-professed "author, media pundit, journalist, campaigner and prominent public speaker", she has made a "new way of life" out of selling herself, her past, and her story. And she’s doing a good job.

Machon, who studied Classics at Cambridge, is the most recent in a long line of famous spies to have emerged from the University – most notably the Cambridge Spies who defected to the Russians during the Cold War.

Best known for her whistle-blowing on issues such as MI5’s alleged involvement in the attempted assassination on Gaddafi, Machon is an oft-consulted expert on current affairs topics such as Wikileaks, the infiltration of activist groups, and the 9/11 Truth Movement, critiquing what she sees as contemporary society’s descent into a "police state".

Commenting on the "very British mess" that is the current UK Intelligence Services, Machon’s answers to my questions blend personal anecdote with hard-hitting assertions. She sounds convincing. Despite no longer having any insider information, she still has plenty to say.

Recruited during the "marginally golden ethical era" of the 1990s, Machon’s experience of MI5 was nevertheless riddled with antiquation, confusion, insularity and suffocation.

Drawing attention to MI5 and MI6’s "culture of just-follow-orders", an ethos that former head of MI5 Dame Stella Rimington also acknowledged, Machon believes that the UK Intelligence Services have, for a long time, been their own worst enemy.

Entrenched in unnecessary laws, a "hangover" from the organisation’s counter-espionage origins, Machon states that until the spooks "open up a little bit to constructive criticism from the other side, so that [MI5] can get a bit of fresh air, they’re going to spiral down into… torture and things."

While Machon asserts that there was no use of torture in her time with the agency – it was considered "counter-productive" and "unethical" – she did hear some horror stories from the older boys’ experience in Northern Ireland including one case concerning an agent, codenamed Steak Knife, who was permitted to torture and even kill his fellow intelligence officers in order to keep his cover in the "Nutting Squad" of the IRA – "A sick James Bond gotten out of hand."

Machon refers to these stories as "a sort of petri dish of the abuses that we are seeing now with the Muslim community". Just as the trend to target one group of society returns, the use of torture, as experienced in Ireland, comes full circle. "It makes me shiver," Machon tells me, "that people who were perhaps my friends, idealistic twenty-somethings when I was an officer, who I might’ve had drinks with, had dinner with, whatever, might be those people now."

While there seems to be a "democratic will" to get rid of "some of the more Draconian laws from under the last government", Machon believes that instances such as Mark Kennedy’s undercover infiltration of an activist group demands society to take a closer look at the ways in which we protect national security. "Once you start eroding someone’s civil liberties on one front, it’ll cascade. That’s how Germany found itself in a Fascist state in the 1930s," the former-spy asserts. "They didn’t wake up one morning and Hitler was in power. It’s a very slippery slope." This is why Machon, above all other issues, is calling for an "adult debate" about the workings of Secret Intelligence in a "mature democracy".

One organization that Machon sees as contributing to this debate is Wikileaks. Machon praised this form of new media, calling it "fantastic" as a "high-tech conduit to enable whistleblowers" in contrast to the "self-censorship and fear" of the mainstream press, which blocks the flow of such information to the public.

Machon advised students at the Cambridge Union to find alternative sources of information for their news, citing countries’ deceptive use of false-flag terrorism. "I’m not saying that every major terrorist atrocity might be a dirty trick, but you have to keep that possibility in the back of your mind," she warned.

"It’s all about a sort of breach of trust," Machon concludes, which is "corrosive for a democracy." Whether it’s an issue like 9/11, or the bailing out of the banks or the war in Iraq, Machon asserts that the erosion of civil liberties is finally forcing society to "become democratically engaged again, which cannot be bad."

In many ways Annie Machon is serving her country as stealthily and determinedly as if she had never left MI5. Taking the "same sort of fundamental drive to try and make a difference, to try and change things for the better," into this new arena of her work, she hands me a red-and-black business card with her shades-toting self on it and the phrase "Using Our Intelligence" emblazoned on the front.

"There’s always the debate," she tells me cryptically, "is it better to be inside the tent pissing out or outside the tent pissing in?"