In the scant collection of carefully-staged photos that emerge from North Korea, Jang Song-thaek was everywhere.

At the funeral of Kim Jong-il, marching directly behind Kim Jong-un, the newly anointed Dear Leader; on an escalator, visiting a shopping centre to glorify the triumph of the regime; dressed in the uniform of a full general whispering words of wisdom into the ear of the world’s youngest head of state.

Now Jang, Mr Kim’s uncle and one of North Korea’s most powerful men, has been erased.

The reclusive communist state confirmed his execution on Thursday. The 30-year-old Mr. Kim, it appeared, was demonstrating in no uncertain terms who really ran the show.

But another tantalizing suggestion is crystallizing. Was Jang’s death by firing squad a sign that the real power behind the throne lies with the two women in Mr. Kim’s life?

"The final decision on Jang Song-thaek was made by Kim Jong-un and Jang’s wife, Kim Kyung-hui," said Lee Yun-keol, the head of the North Korea Strategic Information Service Centre, based in Seoul. "Jang was chosen as a prey by his wife and nephew to maintain the Kim dynasty regime."

The 67-year-old Kim Kyung-hui is a force to be reckoned with – daughter of the country’s first leader, sister of its second and aunt of its third.

A Rosa Klebb-like figure, she went into communist politics early and defied her father, the Eternal President of the Republic, Kim Il-sung, to marry Jang.

The couple had met at university in the capital, Pyongyang, and continued their relationship. She followed him to Moscow, where they both studied, they were married in 1972 and they went on to have a daughter, Jang Kum-song.

But on leaving Pyongyang to study in Paris, their daughter refused to return and committed suicide in 2006 when her parents failed to accept her boyfriend.

Kim Kyung-hui had by then held a number of senior positions within the regime – a general in the army, head of the "organisation and guidance department" and ruler of a key economic policy unit. She also bears the distinction of owning North Korea’s first hamburger restaurant, the Samtaeseong Diner – although, with hamburgers considered American and degenerate, they are marketed as "minced meat and bread."

She kept a low profile for decades until 2009, when she began appearing with her brother during "on-the-spot guidance" trips nationwide.

Two years later, she and her husband were all-powerful, supporting their nephew as he took the reins of power.

"Jang is clearly someone whose major task on behalf of the Kim family is to guide and shepherd Kim Jong-un, and to insulate and protect him," said Stephen Bosworth, the former US special envoy to North Korea, at the time. "His role is to help him ward off assaults on the authority of the family."

But he was also a known womanizer, fond of a drink and indeed purged once before, in 2004, as a result of his hard-living.

On his execution, state media accused Jang of leading a "dissolute, depraved life" and running up £6.4 million in gambling debts.

"He let the decadent capitalist lifestyle find its way to our society by distributing all sorts of pornographic pictures among his confidants," the charge sheet said.

Did Kim Kyung-hui simply get fed up with his wild ways? She has been dogged by rumours of ill health – some suggested she was an alcoholic – but her influence was undeniable. The execution of Jang, some analysts say, would only have been possible with the blessing of his wife – described in The Atlantic magazine as "just as hard-edged and vindictive as her older brother ever was."

Mr. Kim’s pretty young wife, Ri Sol-ju, despite her dainty appearance, is thought to be exerting equally as strong – even ruthless – an influence on the Dear Leader. She was apparently introduced to him by his aunt, and the couple married about three years ago.

But in August, members of a musical troupe of which she was once a member, the Unhasu Orchestra, were wiretapped and heard saying: "In the past, Ri Sol-ju used to play around in the same manner as we did."The regime – and by extension, Miss Ri – was not amused.

"This is an unpardonable, hideous provocation hurting the dignity of the supreme leadership," said the North Korean state news agency. "Those who commit such a hideous crime will have to pay a very high price."

Miss Ri had to have her reputation intact – and so the nine members of the orchestra were arrested, and executed by machinegun three days later, with their families forced to watch.

One of the executed singers was Hyon Song-wol, reportedly a former girlfriend of Mr Kim. She had met the then-future leader a decade ago, but was forced by his father to end the relationship and instead went on to marry an officer in the military.

Hyon’s band was responsible for a string of patriotic hits in North Korea, including I Love Pyongyang, She Is a Discharged Soldier and We Are Troops of the Party. Her popularity reportedly peaked in 2005 with the song Excellent Horse-Like Lady.

But in July last year, rumors emerged suggesting that she and Mr Kim were having an affair after he was pictured with a mystery woman while watching a performance by the Moranbong Band.

One theory is that Miss Ri objected to the continuing high profile of her husband’s former girlfriend.Of course, Mr Kim has no qualms about organising purges of his own.

In October last year Kim Chol, a deputy defence minister, was killed by mortar round for "carousing" during the official period of mourning after Kim Jong-il’s death.

On the orders of Kim Jong-un to leave “no trace of him behind, down to his hair,” according to South Korean media, Kim Chol was forced to stand on a target and was then “obliterated.”

The country’s infamous prison camps, where an estimated 200,000 people are held in conditions of medieval barbarity, are thought to be expanding, while earlier this month, South Korea’s head of national intelligence said that the number of public executions had more than doubled – from 17 last year to more than 40 now.

The latest purge prompted Carl Bildt, Sweden's foreign minister, to dub Mr Kim's regime “the empire of horror.”

Predicting what comes next in this very public internal power play is difficult. Some have speculated that Kim Kyung-hui herself could be purged. The Dear Leader’s wife must also be watching her back.

Jang has been swiftly wiped from history, removed from the official photos and videos, and denounced as "despicable human scum". Tried for an attempted coup and a catalogue of "thrice-cursed acts of treachery", he was last photographed as a broken man - stooped, stumbling and bearing signs of torture.

As Western observers try to unlock the riddle that is North Korea, the question is: who’s next?