After fifteen years on the air, NBC’s hospital drama ER came to an end in 2009. ER was created in 1994 by author and real-life physician Michael Crichton, who also wrote the novels that inspired Jurassic Park, Westworld, and The Andromeda StrainER had been one of the largest televisions shows ever made at that point in time. The show is also responsible for turning then-working actors George Clooney (ER's Ross) and Julianna Margulies into two of the biggest stars in Hollywood.

At its peak, ER ran on a budget of $13 million per episode, which is enormous for a network show and even rivals today’s high-end productions. For a point of comparison, Game of Thrones had a budget of $15 million by the end of its run. Unfortunately, the party wasn't designed to last forever. NBC finally pulled the plug on the hospital drama in 2009. However, for many ER viewers, the magic was already long gone.

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Like many shows, ER has been given a new life thanks to the advent of streaming. Though it has been over ten years since the show ended, people of all ages are just now discovering the era-defining drama. Here’s why ER didn’t survive into the 2010s.

Why ER Didn't Return For Season 16

ER may have been the biggest show on TV during much of its run, but by the time the final episode aired, its viewership just didn’t reflect that anymore. George Clooney left ER in 1999, and the show's ratings never recovered. When Julianna Margulies departed a year later in 2000, the writing was on the wall that ER might not last much longer. Against the odds, the series carried on for another nine years. Industry insiders were skeptical that the ER could even survive after the fourteenth season, but the show earned an extra year thanks to the writers’ strike of 2007. With the fourteenth season left unfinished, the show still had several loose ends left to tie up, inadvertently creating demand for more episodes.

The extra year was as much luck as ER was going to get. By 2007, ER had dropped all the way to 54th place (via ABC's official ratings release) from its former spot in the top-ten watched ABC shows. NBC did not grant ER a sixteenth season, and the show used its final episodes to wrap up all its stray story threads. It also threw in a few guest appearances from former cast members including George Clooney. The series finale of ER ended up doing great ratings-wise, closing out the series on a high note. Executive Producer John Wells even seemed to agree that it was time to move on, telling the New York Times, "It's very odd to say, but it really was time to end. It's ending at a time when we're all still very proud of it.”

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