Director Guillermo del Toro disowned the film after constant clashes with Bob Weinstein, who would frequently visit the set and make unreasonable demands about what should be shot, deviating away from the script. Since then del Toro has never worked with the Weinsteins.
Originally planned as a single 30-min. short as part of a feature of sci-fi/horror/comedy shorts by Miramax. The other segments also grew into the features Impostor (2001) and Alien Love Triangle (2008).
The escalator in Delancey Street subway station is shown as dismantled for maintenance because the scene was filmed on a Toronto subway station platform that was closed in 1966, so its escalator was removed (See also Thrill Seekers (1999)).
The trivia item below may give away important plot points.
In the original ending Doctor Susan and the kid come up from the subway into Grand Central Terminal only to be confronted by hundreds of commuters dressed like Long John. This ominous ending didn't test well so the 'happy' street scene ending was shot and appears in the final cut.