This latest documentary ends with "Jihadi John" standing over the lone, bloodied head of Kassig; but it lasts a full 15 minutes, a rambling compilation tape of scenes of murder and mayhem, overlaid with a tendentious commentary on the war of Isis (Islamic State) against the world - against the Shia, the Alawites, governments, the Crusaders.
The war on the ground has shifted from the fast pace of Isis' advances in the northern summer to more of a gridlock, and the pace and focus of the propaganda message has changed accordingly.
The video is a narrative of the long war that must be fought to bring about Islam's worldwide domination. This time the gore is not just to scare the enemy, but to test the mettle of recruits: are you as ruthless as the men on whose eyes the camera lingers after they have methodically decapitated their victims? The killers stare at the camera; one smirks.
The film would be a field-day for a psychologist specialising in sadism, or fear, or both.
Though perhaps fear is the wrong word: the Syrian soldiers about to be killed, lined up in theatrical style, also get the lingering-camera treatment.
Their steadfastness is remarkable - clear defiance, in one or two cases - for men who must know that the knives are about to be plunged into their necks.
Few people would be able to watch the ensuing scenes, close-ups of heads being severed, as unblinkingly.
The sequence which reveals the killing of Kassig is brief, one and a half minutes tacked on to the end of the film at short notice.
The filming style is markedly different from the rest, having been more carefully put together, perhaps over weeks.
Hisham al-Hashemi, a leading expert on Isis, said he was informed by an insider that Kassig was killed only on Saturday. If that is true, it makes it possible that his murder was a response to the air strikes which are believed to have struck two sets of Isis leaders the weekend before - one on a meeting in al-Qaim, on the Iraq-Syria border, and one on a convoy near Mosul. Several senior leaders are said to have been killed.
There were unconfirmed reports that Abu Bakr al-Baghdadi, the leader of Isis known to his followers as Caliph Ibrahim, was injured.
There is nothing in the video itself to date any of its parts. Usually there is some reference to recent events to prove a recording is contemporary: an audio recording of Baghdadi made after the al-Qaim strike referred to recent announcements.
In some ways, the most important aspect of the video is where the last shots were filmed: "John" and Kassig's head are pictured atop a hill which the video identifies as Dabiq, a village in an Isis-controlled part of Aleppo province.
An anti-Isis activist group posted a satellite image of the area suggesting it was indeed filmed there.
Dabiq has come to figure ever more prominently in Isis propaganda: it is the name of its new, English-language online magazine. This is no coincidence, for Dabiq in the Sunni Muslim "hadith" - or traditions - is the site of the Last Battle, when followers of the faith will defeat the infidel, heralding the end of days.
Since the jihadists took the real-life Dabiq from the Free Syrian Army in August, the idea of raising the flag of Islam there has become a regular motif.
It is notable that whereas in previous videos "Jihadi John" said that the hostages were being killed as a warning to America and Britain not to intervene in Iraq and Syria, this time he urges them to send their troops.
"Here we are - burying the first American crusader in Dabiq," he says. "Eagerly waiting for the remainder of your armies to arrive."
The most obvious difference from previous videos is that we are not shown Kassig alive, in an orange Guantanamo Bay-style jumpsuit, making a final statement to the camera. All four previous hostages spoke, blaming their fate on their Governments.
"John" half addresses this point. "This is Peter Edward Kassig," he says - deliberately omitting Kassig's Muslim name. "Peter, who fought against the Muslims in Iraq while serving as a soldier under the American army, doesn't have much to say. His previous cellmates have already spoken on his behalf."
Some analysts and friends speculated that this might mean he refused to make a statement - and perhaps was killed instantly for that, and beheaded later.
"I think he refused," said Michael Downey, one of his best friends from Beirut. "He was a man of principle and wouldn't give into intimidation from thugs. He never took the easy route."
That would also explain another key difference - why his head is not placed on his body, as was the case with the other hostages and other Isis victims in the earlier videos.
The bulk of the film leads up to and dwells in excruciating detail on the beheading of 18 Syrian regime "officers and pilots". It employs "slow motion" and other technical effects presumably to add drama.
It lingers on the cuts in the men's necks, and this is the first time we see "Jihadi John" carry out a full beheading himself. It is as if he has read the speculative suggestions made about the other videos that he is only a "front man", and does not perform the deed himself. He appears to show no hesitation.
On Sunday, the Daily Mail reported that "Jihadi John" had been injured in the al-Qaim air strike. If Kassig was killed on Saturday, the video would suggest "John" was not badly hurt. He is still able to stand, grasp and point his knife, and address the camera.
The video also seems to confirm that within Isis, "Jihadi John" is no ordinary fighter.
He is chief executioner leading the other killers out in a column. He wears his customary black; they are in army fatigues. He gives the order to start cutting. He behaves as a man with some authority.
Propaganda by Isis is usually precisely targeted, and the latest film is no different. The fact that it focuses on the broader picture rather than individual recent battles is a sign that Isis is not making much progress on the ground.
As such, the video is a rallying cry for resentful Sunnis who feel that they are the misrepresented victims of regime terror.
Peter Kassig
Age: 26.
Who: American aid worker and former US Army Ranger. He served in the US Army in 2006-07. He studied political science at Butler University and was a certified emergency medical technician.
Also known as: Abdul Rahman Kassig. He converted to Islam while in captivity.
Captured: Last year while delivering relief supplies to refugees in Syria.
His parents: Ed and Paula Kassig, of Indianapolis, said they are "heartbroken" by his death but "incredibly proud" of his compassion and humanitarian work. Kassig "lost his life as a result of his love for the Syrian people and his desire to ease their suffering".
The White House: Confirmed Kassig's death. President Barack Obama called Kassig's killing "an act of pure evil" and said the Islamic State group "revels in the slaughter of innocents, including Muslims, and is bent only on sowing death and destruction".
The new footage
What it shows
• The head of the American aid worker and former ranger Peter Kassig at the feet of a hooded killer "Jihadi John" of Isis.
• The makers of the video have prolonged and dramatised a section at its heart showing about 14 men in blue jumpsuits described as Syrian pilots and officers being led by the scruff of their necks by Isis fighters into what appears to be an olive grove.
• Each Isis fighter selects his blade from an awaiting box full of them. Finally each fighter forces their prisoner to the ground and saws through their necks with serrated daggers. The scene is unfathomable in its inhumanity.
The similarities
• Common to all of the hostage beheading videos is their savagery.
• The latest footage again attempts high production techniques. There is a narration with English subtitles as well as a soundtrack.
• As before, prominent in footage is the British-accented individual in a black hoody, widely nicknamed "Jihadi John".
The surprises
• It does not show Kassig being killed.
• He is not shown making a last statement to the camera.
• Nor this time was a new captive identified for execution in the future.
• In the previous tapes the hostages' final moments were shot with different cameras from multiple angles. Yet here, the footage at the tail end of this tape showing the head of Kassig seems hastily shot in bad lighting and taken with only one camera.
Questions raised
• Is it possible that Kassig had attempted to escape, making the usual staged last statement and beheading impossible?
• Does the less-scripted end suggest that its makers were suddenly sent on the run?
• There have been media reports that "Jihadi John" may have been among Isis combatants injured by a coalition air strike nearly 10 days ago. If so, was this tape made before those strikes and what has become of "Jihadi John" now?
- Independent, AP
