HE committed the worst atrocity in Norway since World War Two and his deeds still haunt the nation.
Here's what we know about neo-Nazi Anders Behring Breivik, whose horrifying slaughter is the subject of two new films.
Anders Behring Breivik, now 39, was born on February 13, 1979, in Oslo, Norway.
He was a rebellious teen who struggled with mental health issues after his parents divorced.
In July 2011 he killed 77 people in twin terror attacks on the same day.
He had written a chilling manifesto explaining his evil mission of slaughter.
Over 1,500 hate-filled pages, Breivik declared war on Muslims and vowed to bring down Western civilisation by the year 2083.
The next year he was convicted of mass murder and terrorism and sentenced to 21 years in jail.
If after that sentence he is still deemed a danger to society, Breivik could be handed more jail time.
The murderer has legally changed his name to Fjotolf Hansen while in prison.
He describes himself as a traditional neo-Nazi who prays to the Viking god Odin.
What were the 2011 Norway attacks?
Breivik claims he spent nine years planning the terror attacks on July 22, 2011.
He first set off a car bomb outside the government headquarters in Oslo, which killed eight people and wounded dozens of others.
Then Breivik dressed up as a police officer and drove to the island of Utoya 25 miles away where he shot dead 69 people the annual summer camp of the leftwing Labor party’s youth wing.
He surrendered to police before claiming to be the commander of a secret Christian military order plotting an anti-Muslim revolution in Europe.
What films have been made about the attacks?
In October 2018 two film-makers produced their individual responses to the atrocity.
Director Paul Greengrass' 22 July begins on that fateful day, and deals with Breivik's trial, his lawyer Geir Lippestad and Viljar Hanssen, a student who gives evidence after being shot five times.
Greengrass described the film as "a story about how Norway fought for her democracy".
Utoya - July 22 is focused on the victims, said Norwegian director Erik Poppe.
His film portrays one fictional girl's experience on the island of Utoya in one unbroken 90 minute take.
22 July is released in select cinemas and on Netflix on October 10, while Utoya - July 22 screens at the London Film Festival and opens in the UK on October 26.
Why did Anders Behring Breivik take the Norwegian authorities to court?
Breivik claimed that his human rights had been breached by being held in solitary confinement for five years.
After a prolonged court battle, he lost his appeal to the European Court of Human Rights in June 2018.
Norway says that strip searches and no contact with other inmates are justified for the extremist, who could be attacked by other prisoners or attack others.