One sequence that features some handheld camerawork also involved greenscreen photography. It follows Broome onto a city bus, where she is confronted by someone from the rebel group. Secret Service agents trailing their respective charges also board the bus, which travels four or five stops during the verbal exchange. Meanwhile, suspicious that a bomb has been planted on the vehicle, Teller phones a fellow agent and instructs him to get Broome off the bus. Shortly thereafter, the bus explodes in a ball of fire, killing the remaining agent and passengers.

According to Khondji, the filmmakers’ goal was to make the explosion “really real and very scary.” In fact, during prep, they studied press photos of recent vehicle explosions in Iraq and Israel. “Honestly, I was a bit disturbed by the idea of blowing up a bus in New York,” says Khondji. “I didn’t like the idea, and I felt that way until I got into the technicalities of where to put the cameras, cast and crew safety, and so on.”

After much deliberation, the team decided to use greenscreen for the action inside the bus. “We wanted to shoot two handheld cameras freely and not have to think about the changing of light outside,” says Khondji. “Plus, we wanted to see outside. Sydney was very nervous because he didn’t know how it would come out. He’s not an effects director.” But Khondji, who has ample experience with greenscreen, considers the results “very credible work.”

To capture the view outside the bus, a plate unit worked with three Arri 435s on an insert car, filming three overlapping plates of the Brooklyn streets. All of the action inside the bus was shot at the Hudson River Stages under the direction of visual-effects supervisor Jon Farhat. The greenscreen was U-shaped, and the bus was placed on a turntable-like swivel. De Blau and his crew built two long lightboxes that ran the length of the bus positioned 8' above, each containing about 20 2K open-bulb Nooks that were on separate dimmers “so we could control the light and make it travel along the box,” says the gaffer. “We had smaller sources on the floor that we’d pan left and right or along the bus ceiling to create the sense of moving by a hot, sunny street, or to create a kick off a car.” Kino Flos replaced the bus’s practical ceiling lights, and two overhead hatches were added to let in exterior light. “It was easier to open a trap door than to rig up more lights,” says De Blau.

To record the explosion coordinated by special-effects supervisor Bruce Steinheimer, the filmmakers positioned an Eyemo in a crashbox in front of the bus and seven Arri cameras, a mix of 435s and 35-3s, around the location — inside shops and cars, and even on the roof of the adjacent building. “It was a challenge to get the Strada crane onto the roof,” says Lillian. The aging five-story tenement “had to be shored up throughout the floors, and then the rooftop had to be shored up. Then we used another crane to bring the Strada up onto the roof, where it could be assembled.”

At the eleventh hour, however, the crew hit some snags. The gas company discovered minor leaks in the vicinity, and although the leaks were fixed, the plan to flip a car had to be amended so that the car simply crashed into something. “We were going to do that with a cannon, which is basically a big piston that hits the ground,” says Lillian. “But the gas company didn’t want that percussion over the underground gas lines.”

There was no greater contrast to these pyrotechnics than the velvety calm inside the U.N. Khondji keeps a memento of his days there close at hand: the screensaver on his computer is a photo he took from the production office on Dag Hammarskjold Plaza. It shows the U.N.’s glass tower catching the late-afternoon light, and the building is radiant in a sea of silhouetted buildings. “That’s the image I had of the U.N. in my mind,” says Khondji. “It’s an angelic, beautiful place in the middle of all this darkness in the world. I tried to push the contrast between good and evil in the film, and that,” he says, gesturing to his screensaver, “was the image for me.”

TECHNICAL SPECS Anamorphic 2.40:1 Arricam Studio, Arri 435, Arri 35-3 Cooke lenses Kodak Vision2 Expression 500T 5229, Vision2 100T 5212 Digital Intermediate by EFilm