Today marks 10 years since Kim Jong Un, the third generation of his family to rule North Korea, took power after his father's sudden death from a heart attack.
Initially considered inexperienced, Mr Kim quickly showed his ruthless willingness to consolidate his rule by having his powerful uncle and other potential rivals executed or purged.
His torrid run of nuclear and missile tests in recent years caused many to fear a second Korean war.
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Mr Kim switched gears again and staged landmark nuclear disarmament summits with former US president Donald Trump, but their diplomacy collapsed because of disputes over US-led sanctions.
Now, with the pandemic and sanctions causing deepening problems, Mr Kim has sealed off his country's borders and tried to fix its struggling economy.
As he enters a second decade in power, here's a look at key moments in his rule.
High-profile purges and executions
In late 2011, many outsiders wondered if North Korea would survive with an untested, little-known 27-year-old in charge.
Some predicted Mr Kim would push for economic reforms and possibly denuclearisation because of his youth and childhood education in Switzerland.
Others thought Mr Kim might be a figurehead, relying on elderly officials installed by his father, and worried that North Korea could face political turmoil.
Instead, Mr Kim orchestrated a spate of high-profile executions and purges, eliminating potential rivals and establishing the kind of absolute power enjoyed by his father and his grandfather and state founder, Kim Il Sung.
A think tank run by South Korea's spy agency said in a 2016 report that Mr Kim executed or purged about 340 people during the first five years of his rule.
That included the 2013 execution of his powerful uncle, Jang Song Thaek, and the 2012 purging of military chief Ri Yong Ho, both of whom helped shepherd Mr Kim into power.
North Korea was also widely believed to be responsible for the public assassination of Kim Jong Nam, the estranged half-brother of Mr Kim.
He was killed at a Malaysian airport after two women smeared VX nerve agent on his face – an act which was caught on CCTV.
A Malaysian woman and an Indonesian woman were arrested, but both consistently stated that they were tricked into killing Mr Kim, saying they were told they would be taking part in a reality television prank show.
The Malaysian woman was sentenced to 40 months in prison but was released a year early for good behaviour.
Her co-accused had her charges withdrawn altogether and was freed without conviction after the Indonesian government lobbied Malaysia on her behalf.
The North denied involvement.
Nuclear weapon diplomacy
An arsenal of as many as 60 nukes, by some estimates, with the means to add as many as 18 more a year, has allowed Mr Kim to solidify domestic unity and achieve some measure of the global prestige he's long coveted.
Throughout his leadership, Mr Kim hasn't been shy in staging an unusually large number of weapons tests.
Four of North Korea's six nuclear test explosions, and all of its three intercontinental ballistic missile tests, have happened during his rule.
He called his first flight test of an intercontinental ballistic missile in July 2017 the North's "package of gifts" for US Independence Day and claimed to have nuclear missiles capable of reaching the American homeland.
Later that year, such threats were met with strong words from Mr Trump, who warned that North Korea could "be met with fire and fury like the world has never seen".
North Korea later responded by threatening to launch a salvo of missiles toward the US territory of Guam.
In 2018-19, Mr Kim engaged in ambitious nuclear diplomacy with Mr Trump, holding the first summits between the two wartime foes and also meeting South Korean President Moon Jae-in and Chinese President Xi Jinping.
The International diplomacy broke down in 2019 when Mr Kim failed to convince Mr Trump to ease tough UN sanctions imposed after his run of weapons tests in 2016-17.
Mr Kim has since threatened to enlarge his nuclear arsenal and introduce high-tech weapons targeting the United States and its allies.
The US has recently repeatedly offered talks with North Korea "anywhere and at any time" without preconditions.
Economic struggles and 'tense' food shortages
Despite years of sanctions, the North Korean economy still relies on trade, particularly with its key ally China.
It needs key inputs like fertiliser and fuel – without them, it cannot produce the food needed to feed its population.
A UN rights investigator has warned that vulnerable populations in North Korea risk starvation if the economic and food situation is not reversed.
The pandemic has seen the government further strengthen its grip on the economy, casting doubt on the future of the black markets as well as official businesses that many North Koreans had come to rely on.
In January 2021, Mr Kim admitted that his economic development plans had failed during the North's first Workers' Party congress in five years.
He has acknowledged acute food shortages and described the situation as "tense", telling his citizens to prepare for the "worst-ever outcome".
Mr Kim blames the country's struggles on the pandemic, persistent sanctions and natural disasters.
Slim Kim sparks health concerns
This year, Mr Kim appeared in public after not being seen for a month, looking noticeably slimmer, raising questions about his health.
Analysts say it is still unclear why Mr Kim's waistline shrank, but it was clearly being used to paint him as a stressed leader, toiling away during tough times.
North Korean state media appeared to spin the unexplained weight loss of up to 20 kilograms, saying it was a result of the nation's food shortages.
"Our people's hearts ached most when we saw [his] emaciated looks," a North Korean man said on state television.
The chain-smoking, hard-drinking leader reportedly suffers from an array of health conditions, including gout.
He vanished for 40 days in 2014, even missing an important parliamentary session, before re-emerging with a walking stick.
Mr Kim could theoretically rule North Korea for decades to come, just as his father and grandfather did.
But amid Mr Kim's changing appearance this year, speculation swirled around who would emerge as a potential successor.
Many have pointed to his sister Kim Yo Jong, who, at the time, verbally attacked South Korean President Moon Jae-in and ordered the detonation of the inter-Korean Communication Office last year.
Given North Korea's dominant patriarchal culture, analysts say the conservative ruling class would make her path to power a potentially dangerous one.
The hermit kingdom's approach to COVID
Mr Kim shut North Korea's borders and imposed strict prevention measures soon after the pandemic began.
Last year, the authorities declared a state of emergency and locked down the border city of Kaesong after a person who defected to South Korea returned across the fortified border with what state media said were symptoms of COVID-19.
Nearly two years later, North Korea's health authorities still claim they have not confirmed a single COVID-19 case.
However, the UN special rapporteur on human rights in North Korea has said the country's most vulnerable people risk starvation after it slipped even deeper into isolation.
North Korea and Eritrea remain the only countries that have yet to start their vaccination campaign against COVID-19, according to the WHO.
ABC/wires