"There are a lot of reasons why ER became a huge, instant hit and remained one for a decade-plus," says Jen Chaney, reflecting on the NBC medical drama's 25th anniversary. "One is that the medical drama, when done right, will always find an audience. Certainly the cast of ER — which, in its early seasons, included Anthony Edwards, Noah Wyle, Juliana Margulies, Eriq LaSalle, and some guy named George Clooney — was enormously appealing. But I would argue that the directorial style of the series is what hooked people and kept them coming back every week. The way the camera zipped from one moment to the next implied that something unexpected could happen at any time, and it often did. You didn’t want to look away for a second or skip an episode. You might miss something." Director and producer Mimi Leder helped establish ER's look and feel after the pilot episode. As Leder explained to Indiewire, "my memories of the beginning of ER were of the building that set — (executive producer) John (Wells) and I looking at the floor and going, ‘That’s a great floor! Let’s use that!’ And I remember our D.P. going, ‘That’s awful.'" Another key part of ER's visual look was the use of steadicams. "Steadicams were not commonly used in television in the early ’90s, but they were central to ER and became a signature part of its approach, even if the average viewer wasn’t necessarily aware of what how they were being used behind the scenes," says Chaney. "When you picture ER, the first images that come to mind are probably of doctors working on a patient while shouting medical terms, as a camera swirls in circles around the operating table. That sense of fluidity was there from the beginning, even in smaller moments, because the cameras refused to just stay still."