Thousands have protested across the Middle East and North Africa against a film made in the US that depicts the Prophet Muhammad. James Longman explains what is in the film and why it has enraged so many people.
What does the film show?
The video, a trailer for a longer film entitled Innocence of Muslims, appears to depict Islam as a religion of violence and hate, and its Prophet Muhammad as a foolish and power hungry man.
It opens with a scene in which a Coptic family in a newly radicalised Islamic Egypt is attacked by a group of Muslims. The father tells his daughters that Muslims are bent on killing all Christians and that the Islamic state is hiding their crimes.
It then depicts the Prophet Muhammad and his life with his family and his followers in the desert. He is shown with his wife Khadija, and implies she engineers the Koran with a mix of Old and New Testament verse. He is also shown in sexual positions with his wife and other women.
The film shows Muhammad's followers to be savage killers hungry for wealth and bent on killing women and children. One of the most insulting sequences includes a reference to Muhammad sanctioning the molestation of children, and at one stage the Prophet also declares that he is gay.
Many characters recite verses supposedly taken from the Koran although clearly invented, as they go about killing and extorting locals.
Why is it so offensive?
Depicting the Prophet Muhammad in any way already defies Islamic belief, let alone satirising him. His wife Khadija and his earliest companions are also revered in their own right in Islam, and so mocking these individuals is also considered serious blasphemy.
The founding principle of Islam is that the Koran is the direct word of God, revealed to Muhammad in order that he impart it to humankind. Depicting Khadija as planning to concoct a holy book out of the Old and New Testament defies an intrinsic Islamic belief.
Other references to Muhammad's affairs with women, his greed and violence would clearly be insulting in any context.
What do we know about how it was put together?
The entire film is thought to be around an hour long, although most have only seen a 14 minute trailer which has now been widely circulated on the internet in English and Arabic.
It was clearly put together on a budget, with a cheaply made set, amateur actors and poor production standards. It was shot over five days at a California film studio in August last year, with a cast of around 50, together with a large production crew.
The most offensive parts of the film appear not to have been in the original, but dubbed over the soundtrack at a later date.
Who is Nakoula Basseley Nakoula?
The now infamous trailer for the film was posted through a Youtube account linked to the name 'sambacile' - originally reported as an Israeli Jew who had raised $5m dollars from Jewish donors in the US to make the film. But this person did not exist.
US authorities now say they have identified Nakoula Basseley Nakoula, an Egyptian-born Coptic Christian living in California as the man who made the film. Basseley, who was found guilty of fraud in 2010 and ordered to pay more than $790,000 in restitution, is thought to have used the pseudonym "Sam Bacile" to hide his identity. He denies the allegations.
What do the actors say about it?
They say they were misled about the film entirely, claiming that the original film had nothing to do with Islam or Muhammad, and that all references to him and insults to the religion were added post-production.
Cindy Lee Garcia, who had a small role in the film, told Web site Gawker.com that she and others were given a script for a film called Desert Warriors, and that it would be a historical drama set in the Middle East. Ms Garcia also said she had seen Mr Nakoula on set.
Is there something more going on here than protests about a film?
As was evident after Danish cartoons of Muhammad were published in 2006, politicians and religious leaders in the region use perceived insults to Islam to rally public support.
Protests began to spread from Egypt to other countries - spurred on perhaps by local media - because of a long-standing mistrust and anger at the West, something a number of groups have been able to capitalise upon.
Disillusionment, lack of opportunity and anger at the establishment can cause protests in any context.