One of the hottest races at the Emmy Awards last year was the limited series category: “Big Little Lies” eventually triumphed, but when your runners-up include “Fargo” and “Feud,” you know it’s a quality race. Quite a shift from the start of the decade, when only two shows, “The Pacific” and “Return to Cranford,” were nominated in 2010. The year before, only “Little Dorrit” and “Generation Kill” earned noms. Things looked so bleak, the category was combined with the TV movie category for a bit. While the two categories still share acting nominees, the limited series category has been back on its own since the 2014 awards.

In recent years, the category has been dominated by big stars who get the appeal of appearing on television without an open-ended commitment. The same applies to off-camera talent; this year alone, filmmakers like David Lynch (“Twin Peaks”), Scott Frank (“Godless”) and Steven Soderbergh (“Mosaic”) have released limited series.

But how does a limited series differ from a standard drama? The Emmy Rules and Procedures (last updated in 2017) define a limited series as “a program with two [2] or more episodes with a total running time of at least 150 program minutes that tells a complete, non-recurring story, and does not have an ongoing storyline and/or main characters in subsequent seasons.”

But some shows that begin as a limited series don’t know what their future holds. Take last year’s winner, “Big Little Lies,” based on the book by Liane Moriarty. With marquee stars like Nicole Kidman and Reese Witherspoon, the series told the entire story of the book — and talks of a second season didn’t start until after the show became a hit. Now, a second season is due, with an original script and the star ante upped to include Meryl Streep. Which means next season will likely have to compete in the more crowded drama field.

There is precedent for this; “Downton Abbey” won the limited trophy in 2011 and then continued for five additional seasons, becoming a regular Emmy nominee in the drama category.

Of course, not every show goes this route. Netflix raised some eyebrows when it adapted Jay Asher’s “13 Reasons Why” and submitted it as a drama series. After all, where was there to go once the story in the book was complete? But season two landed May 18, continuing the tale.

“In recent years, the category has been dominated by big stars.”

And despite wrapping up Margaret Atwood’s dystopian novel at the end of season one, Hulu’s “The Handmaid’s Tale” planned to be a continuing series from the start. It was a daring choice, but one that paid off handsomely: the show won eight Emmys, including best drama. And the second season has proven no shortage of storylines.

And then there’s the case of “Twin Peaks,” a series that earned nominations in the drama category in the 1990s. Showtime’s reboot will compete this year in the limited category. Given the long buildup to the reboot, a season four with Agent Dale Cooper and friends likely won’t be seen anytime soon.