A wide theatrical release in the United States was canceled due to the 9/11 terrorist attacks. Although entirely coincidental, the film makes several references to terrorism in New York City, getting as specific as mentioning plane hijackings and Osama Bin Laden destroying the World Trade Center.
In real life Naomi Watts is afraid of elevators.
US remake of the Dutch horror film L'ascenseur (1983), which was also written and directed by Dick Maas. Where L'ascenseur (1983) was Maas' very first film as a director, L'ascenseur (niveau 2) (2001) was the first American feature film that he directed.
Though taking place in New York, most of the indoor filming was done in the Netherlands. Many of the bit players (especially among the pregnant women) are well-known Dutch actors. Ike Barinholtz, who made his feature debut here as Milligan's assistant, was already living in the Netherlands at the time, working with the famed comedy improve troupe "Boom Chicago" which also included comedian and future director Jordan Peele.
While the Dutch original L'ascenseur (1983) is considered somewhat of a cult classic in the Netherlands due to its effective combination of low-budget horror and black comedy, this Dutch/American remake was mostly panned by critics for its campy and over-the-top redoing of the same story, although some praised the film for fully embracing its B-movie quality.