"United 93, by the British director Paul Greengrass, opened the Tribeca Film Festival, and the evening began like any other premiere, with a red-carpet procession of celebrities - including Robert De Niro, Steve Buscemi and Gabriel Byrne - and attendant TV cameras and gawking passersby.

But joining them in the 1,600-capacity Ziegfeld Theatre was a group who gave the event a more sombre tone: about 90 people who lost family members when a United Airlines plane crashed into a field in Somerset County, Pennsylvania, killing all 33 passengers and seven crew members, as well as the four hijackers. The relatives were given a standing ovation after Jane Rosenthal, co-founder of the festival with De Niro, said she hoped the film could be part of a 'healing journey'."

The film is a documentary-style re-creation of what Mr Greengrass calls a "believable truth" about what might have happened on the plane and in air-traffic control centres - from the moment a controller hears the first indications of the hijacks to when the Flight 93 passengers storm the cockpit and try to seize control.

"This movie puts a face on the enemy and demonstrates accurately the extent to which the enemy will go to destroy us," David Beamer, the father of passenger Todd Beamer, told the Guardian before the premiere.

"The enemy doesn't have the word surrender in his dictionary, and we can't have the word retreat in ours."