THE surprise at the Asian games, in the South Korean city of Incheon, did not come on the track. Rather it was when three of North Korea’s most powerful men suddenly appeared on October 4th, the day of the games’ closing ceremony.

The seniority of the men visiting South Korea was unprecedented. Though it was at least the third trip south for Kim Yang Gon, North Korea’s point-man on relations with the South, it was the first for Choe Ryong Hae, thought to be the closest aide of the young dictator, Kim Jong Un—until watchers believed he had been purged in May. Most surprising, however, was Hwang Pyong So, head of the political bureau of the Korean People’s Army and probably the North’s second-in-command.

The trio dropped in with only a day’s notice and had, it appears, no particular message. Still, they were warmly welcomed by the South’s unification minister for lunch and tea; Mr Hwang in turn conveyed Mr Kim’s “heartfelt greetings” to President Park Geun-hye. They also met Ms Park’s national security adviser, Kim Kwan-jin, and the prime minister, Chung Hong-won. After months of refusals, the North agreed to a new round of talks soon.

On the face of things, it marks a transformation of the lousy North-South relations since Ms Park took office last year. North Korea has fired a score of rockets into seas around the Korean peninsula this year. A relentless propaganda offensive has taken aim at Ms Park. Now, North Korea may want to patch up with the South as its relations with China sour. Remarkably, the Chinese media made no mention this week of the 65th anniversary of the two countries’ ties; North Korean mouthpieces returned the compliment. But money usually counts for much with the North. It may be keen to see South Korean trade sanctions eased and to restart hard-currency tours to Mount Kumgang, a resort shut off since 2008, when a soldier shot dead a South Korean tourist.

High-level officials from the North have not come south since the funeral of a former president, Kim Dae-jung, in 2009. Indeed, no one as senior as Mr Hwang has ever visited South Korea before, says Michael Madden, who runs “North Korea Leadership Watch”, a blog. Mr Hwang arrived in full military garb and on Mr Kim’s personal plane. Sending its heavyweights for snaps with foreign officials makes North Korea look “more like a sovereign state, less like a gangster fiefdom”, says Robert Kelly of Pusan National University. North Korea is burnishing its image elsewhere, too. Last month its foreign minister attended the UN’s General Assembly, for the first time since 1999, and in Europe a senior diplomat even met the EU’s top human-rights official.

All this has rumbled on while the young Mr Kim has been out of view. He was last seen on September 3rd, attending a concert with his wife. Mr Kim’s late father, Kim Jong Il, would disappear for months. But his son has been much more visible, and this is his longest absence yet. He even skipped a set-piece meeting of the North’s parliament.

Mr Kim, who may be 31, is fat, drinks heavily and smokes even in front of the cameras. In July he was seen limping. Gout and an ankle injury are thought to be reasons for his “discomfort” announced by state media last month—possibly the first-ever acknowledgment of problems with a North Korean leader’s health.

Now Mr Hwang’s sudden appearance in the South has some wondering who wields ultimate power in the North. Mr Hwang has been promoted five times this year, an “unprecedented, almost scary” rise, says Mr Madden. He gained his most senior title yet, that of vice-chairman of the National Defence Commission—the North’s top executive body, headed by Mr Kim—at the very gathering from which Mr Kim was absent.

Mr Hwang is also an official of the Organisation and Guidance Department (OGD), seen by some as a party within the party and established by Kim Jong Il to keep rivals and relatives in check. It has the power to appoint and dismiss all party members. Jang Jin-sung, a former propaganda official for Kim Jong Il who fled the North in 2004, thinks there has been a power grab. Mr Hwang arrived in Incheon flanked by two bodyguards: a move that Mr Jang sees as lèse-majesté, for hitherto only the supreme leader could ever be seen to be guarded. The trio looked in control, “not like anyone’s delegation”, says Aidan Foster-Carter, an analyst of North Korea at Leeds University. They also stinted in public on flattering the Young Leader; and rather than bridle at questions about his ill health, they denied any problem.

Few besides Mr Jang support the theory of a coup, however. Had the Kim family been overthrown, there would presumably have been troop movements, particularly in sensitive border areas. And, despite strained ties, the top brass would surely first turn to China for reassurance, says Hahm Chai-bong of the Asan Institute, a South Korean think-tank. Still, the tantalising possibility arises of Mr Kim being at the centre of a cult, but not the centre of power.

As soon as the trio had returned home, calls grew in South Korea for a response to their unusual gesture. For the first time, members of the ruling conservative party asked to lift trade sanctions introduced in 2010 after a South Korean corvette was torpedoed, killing 46. Yet just three days after the visit, North and South Korean ships exchanged fire when a Northern patrol boat crossed a disputed maritime boundary. The North can surprise. But it can also be wearyingly predictable.