'There aren't any bombshells,'' Mark Arbib says. ''No one has threatened me. No one has cajoled me. No one knew I was going to resign until I went to the PM.''

The now former politician has the same, semi-exasperated, incredulous tone he adopted the last time we spoke, for a Good Weekend profile - although on that occasion we were discussing his notorious outing by WikiLeaks in 2010 as a ''protected source'' of the Americans, highly regarded for his inside information on the workings of the Australian government and the ALP.

"You won't see me on ABC 24, or Sky TV. I won't be writing any books," adds the most machiavellian of the so-called ''faceless men'', unwittingly throwing down the gauntlet to a publisher, perhaps. A Mark Arbib memoir, even one read beneath the bed covers with a torch, could well knock off the sales figures of the other famous Mark's political memoir about the Labor Party, The Latham Diaries.

"I find it incredible that people are cynical about politicians who leave for family reasons. What other reason is so important?" Arbib asks, which only serves to make that question stand out even more than it does already. Unlike our previous encounter, which took place face to face, we're speaking on the phone, so I can't read his expression.

Last Monday, only a few hours after Julia Gillard's win over Kevin Rudd in the leadership tussle, Arbib managed to upstage the rebirthed Prime Minister with his seemingly inexplicable decision to quit federal politics - in order to spend more time with his wife and their two little girls.

Announcing his decision at a hastily organised press conference, the renowned Labor factional powerbroker, son of a Libyan-born migrant from Italy, said that when he was promoted in the ministry late last year, his six-year-old daughter cried because he'd explained this meant he would spend more time at work.

Arbib, who's only 40 despite his reputation as a formidable weaver of political dark arts, says the same when we speak. His decision to leave the Senate was all about family. Although Bob and Helena Carr are ''family friends'', Carr's move took him by total surprise. ''I wasn't involved in any of the discussions … [But] if I had known he was interested in going into the Senate, I would have stepped aside for him.''

Arbib's decision to leave the ministry was to give Julia Gillard the best chance to win the next election, he goes on. "It takes the faceless men out of the equation. She deserves clean air. I've been at the forefront of so many of the deals and it takes away some of the enmity."

He's not the only ''faceless man'', I suggest of the tag that will probably always precede Arbib's name, even when - and if - he does start a new career in the corporate world, as he indicates might happen.

"You know that I've got the stigma," he replies.

Though he wasn't the only ''faceless man'' involved in the push to overthrow Kevin Rudd in 2010, to install Julia Gillard as Prime Minister, Arbib is seen as the most notorious of the plotters - not least because he was also the driver of Rudd's successful 2007 election campaign.

He accepts the stigma, he continues. "I've been the person who made the hard calls and now I'm making the hard call about myself. But I'm paying the price on my own terms and I'm picking my own time. The golden rule of politics is to decide your own fate."

But that too seems to leave an echo when spoken by the man who became assistant treasurer in Gillard's government, while also sports minister and small business minister.

Love of family aside, Arbib's departure from politics has mystified some of his present and former parliamentary colleagues, although the Minister for Infrastructure, Anthony Albanese, says Arbib's decision to go for family reasons is certainly consistent with conversations the two of them have had over the years. In fact, Albanese says, they had exactly that sort of conversation on the Friday before Albanese held his own, emotional press conference, when he declared he'd be voting for Rudd in the secret ballot.

The Immigration Minister, Chris Bowen, says Arbib's departure is a big loss. "He's a first-class political strategist. I tried to persuade him: 'mate, you should stay'," he says.

But a Labor insider prefers to think along murkier lines. "Who would spend 20 years of their life trying to get into politics and then quit? For him to walk away at this stage doesn't make sense,'' this person says.

Arbib had 2½ years to go before his term in the Senate was up and when he resigned, he'd recently been made manager of government business, a key strategic role.

"I've got no idea why he resigned," Nick Xenophon, the independent senator for South Australia, jokes. ''I rang Bob Brown and asked if he was coming over to be the Greens' chief strategist, but Brown denied it.

''It's certainly seen as a bit of a mystery - why now?" he adds.

Xenophon mentions Arbib's work as sports minister, pointing out the admiration for him for tackling match-fixing and corruption in sport. The reluctance in many quarters to accept Arbib simply missed his family too much comes partly because the sports-mad politician would have been a VIP member of the Australian Olympic team travelling to Britain for the London Olympics - now less than 150 days away.

"I can't win on this one. If I had stayed until the Olympics, and then resigned, you guys [in the media] would have said, 'he only stayed in the job to be able to go to the Olympics'," Arbib retorts.

When he turned 30, he says, he promised his wife, Kelli Field, an associate director at Macquarie Bank (and formerly chief of staff to one-time NSW treasurer and police minister Michael Costa), that he'd reconsider his career at 40.

"I've loved being a minister, I've loved the policy work," he says. "But when all the Qantas staff know my first name and my kids are forgetting it … in 2010 after the election, I was very close to resigning then, because I was one of the people who made the tough call - one of the toughest calls - and it was the right call, and I stand by that.

''But there's a price that had to be paid. I hope my decision helps close the chapter on the past 18 months for the party, and for Kevin [Rudd]. It has been a difficult period for all of us."

How did Gillard react to his resignation when he walked into her office last Monday? "It was an emotional decision for her and I. She asked me to stay," he replies.

Has Rudd contacted him?

"I'll have to check my messages. I've got about 250 of them," he says.

All week the speculation has continued to swirl, although his generous farewell speech on Thursday, when he thanked parliamentary colleagues on both sides of the political divide, was certainly noted. As was his tweeting that the real reason for his resignation was his ''role'' in the popular Australian soap opera Home and Away, as seen in a spoof video posted on the internet.

But some aren't laughing.

The former diplomat and political commentator Bruce Haigh, a regular guest on ABC TV's The Drum, says Arbib's explanations aren't credible.

"He's acting as if someone, or some people, have come and said he has gone too far and have threatened to put [some information] into the public domain unless he removes himself from the political scene. The public don't care about Arbib going," Haigh adds of Arbib's claim he quit in the interests of party and government.

"It won't change Gillard's standing [in the public mind] one iota. In fact, it gives traction to Tony Abbott, who can now say, 'who knifed Arbib, and why?'. His going in this way is much more a thorn in Gillard's side than by him staying.''

Arbib's Stab At Nobility Was 'Paying The Price'

meanwhile, attempts to locate the whereabouts of the notorious labor insider & fixer, graham frederick richardson have thus far proved fruitless …..