<P> Abbey and Kona, both three - year - old German Shepherd dogs, played Neville's dog Sam . The rest of the supporting cast consists of Salli Richardson as Zoe, Robert's wife, and Alice Braga as a survivor named Anna . Willow Smith, Will Smith's daughter, makes her film debut as Marley, Neville's daughter . Emma Thompson has an uncredited role as Dr. Alice Krippin, who appears on television explaining her vaccine for cancer that mutates into the virus . Singer Mike Patton provided the guttural screams of the infected "hemocytes", and Dash Mihok provided the character animation for the infected "alpha male". Several filler characters with uncredited roles were in old news broadcasts and flashbacks, such as the unnamed President's voice (Pat Fraley), and the cast of The Today Show . </P> <P> Akiva Goldsman decided to move the story from Los Angeles to New York City to take advantage of locations that would more easily show emptiness . Goldsman explained, "L.A. looks empty at three o'clock in the afternoon, (but) New York is never empty...it was a much more interesting way of showing the windswept emptiness of the world ." Warner Bros. initially rejected this idea because of the logistics, but Francis Lawrence was determined to shoot on location, to give the film a natural feel that would benefit from not shooting on soundstages . Lawrence went to the city with a camcorder, and filmed areas filled with crowds . Then, a special effects test was conducted to remove all those people . The test had a powerful effect on studio executives . Michael Tadross convinced authorities to close busy areas such as the Grand Central Terminal viaduct, several blocks of Fifth Avenue, and Washington Square Park . The film was shot primarily in the anamorphic format, with flashback scenes shot in Super 35 . </P> <P> Filming began on September 23, 2006 . The Marcy Avenue Armory in Williamsburg was used for the interior of Neville's home, while Greenwich Village was used for the exterior . Other locations include the Tribeca section of lower Manhattan, the aircraft carrier Intrepid, the Kingsbridge Armory in the Bronx, and St. Patrick's Cathedral . Weeds were imported from Florida and were strewn across locations to make the city look like it had been overgrown with them . The closure of major streets was controversial with New Yorkers . Will Smith said, "I don't think anyone's going to be able to do that in New York again anytime soon . People were not happy . That's the most middle fingers I've ever gotten in my career ." </P> <P> A bridge scene was filmed for six consecutive nights in January on the Brooklyn Bridge to serve as a flashback scene in which New York's citizens evacuate the city . Shooting the scene consumed $5 million of the film's reported $150 million budget, which was likely the most expensive shoot in the city to date . The scene, which had to meet requirements from 14 government agencies, involved 250 crew members and 1,000 extras, including 160 National Guard members . Also present were several Humvees, three Strykers, a 110 - foot (34 m) cutter, a 41 - foot (12 m) utility boat, and two 25 - foot (7.6 m) response boat small craft, as well as other vehicles including taxis, police cars, fire trucks, and ambulances . Filming concluded on March 31, 2007 . Computer - generated imagery (CGI) was used to depict the main spans of the Brooklyn Bridge and the Manhattan Bridge collapsing as missiles from passing military jets blew them up to quarantine Manhattan island . </P>

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