LOS ANGELES » It's late morning on the last Sunday in September, and two blocks of the downtown area have been cut off from car and foot traffic in order to reproduce a New York City street scene, complete with yellow-cab gridlock.

Extras fill cabs and play sidewalk pedestrians, while in take after take, a small group of technicians rides with a camera mounted on a small electric vehicle, moving parallel to an actor playing a bicycle messenger.

Although it's the weekend, Robert Scott has been hard at work since crew call at 6:30 a.m. Scott, who began his career back home in Hawaii, is a crucial member of the production crew of the hit NBC show “;Heroes,”; now filming the remainder of its third season.

“;Heroes”; has become one of NBC's breakout shows, complete with a devoted international fan base, and Scott has been along for the wild ride, albeit behind the scenes.

This shoot, involving 250 people, is for the upcoming episode “;Our Father,”; the next to last in this season's first 13-part story arc, titled “;Villains.”; Later, one of the series' newer characters, Daphne, she of superpowered, supersonic speed, will be inserted into the scene, chasing the bicyclist as he weaves in and out of traffic.

Scott is pedaling as fast as he can on his own bike to stay several yards ahead of the tracking camera so he can monitor the action. His job as first assistant director is to coordinate all the activity on the set and make sure the large operation moves smoothly as possible, on time and within budget.

“;He is absolutely amazing,”; actor Masi Oka, who plays the popular character Hiro, said during a press conference call a couple of days earlier. “;I call him 'sensei' on set. He is an absolute joy to be around, and the entire cast enjoys working with him. Because of him we actually get the show done on time.”;

Executive producer Allan Arkush was able to illustrate that point. “;I remember one day, during the filming of an episode from last season that involved working on a location that represented feudal Japan. It couldn't have been a more complicated shoot, and coming up on the lunch break, we were already a half-hour to 45 minutes behind schedule. So I told Robert that we had to achieve everything we scheduled that day in the remaining six hours we had, and could we do it? And with his help, we pulled it off. It's that kind of teamwork and team spirit he brings to the set, whether in the studio or on location, that is invaluable.”;

Scott says he's hit on a middle-management style that works. “;While some are screamers, I like to hang back and watch and anticipate things. And I think I'm more of a supportive worker because of my Hawaii background, so I like to think that I bring a positive energy to my job.”;