Who dies in the series finale of 'Stranger Things'?

Spoiler alert! The following contains details from the series finale of "Stranger Things": "The Rightside Up."

In the end, 99% of our Hawkins heroes got the happy ending they deserved.

Actually, maybe 100%.

As the fifth and final season of "Stranger Things" sped toward its New Year's Eve finale episode, fans speculated about who would live and die. Would the beloved Steve Harrington live to see another day with his partner in crime, Dustin Henderson? Would Will and Eleven make it out alive after a faceoff with Vecna?

The sci-fi series, created by Matt and Ross Duffer, has never shied away from killing characters, from poor Barb Holland (Shannon Purser) in Season 1 and the brotherly villain Billy Hargrove (Dacre Montgomery) in Season 3 to fan favorite Eddie Munson (Joseph Quinn) in Season 4.

So it's with probably a lot of shock that the series ended mostly bloodlessly, with only poor Kali/Eight (Linnea Berthelsen) and villainous Vecna (Jamie Campbell Bower) confirmed to have perished in the finale episode. Kali dies at the hands of one of Dr. Kay's (Linda Hamilton) cruel soldiers, who despises her and El for their supernatural powers. Vecna and his Mind Flayer conspirator are killed by Eleven (Millie Bobby Brown) and the rest of the gang in a big battle sequence that ends with the veiny villain skewered on a spike. He's not quite dead after that, though, and it's Joyce Byers (Winona Ryder), who deals a series of fatal blows with an axe, beheading the monster once known as Henry Creel. She even gets a cheesy line before she does it.

But one question is lingering.

Does Eleven die in the 'Stranger Things' series finale?

For the final few episodes of the series, Eleven has been reckoning with a life-and-death dilemma. Rescuing Kali from Dr. Kay's lab led her to discover that the evil scientist is trying to create more super-powered kids to fight the Russians (of course) by using Kali and El's blood. Kali wants them both to sacrifice themselves in the name of ending the cycle for good.

El fights with both surrogate dad Hopper (David Harbour) and boyfriend Mike (Finn Wolfhard) about this over the course of the episode. After it seems like our heroes have won the day and get to ride off into the sunset, they are captured by Dr. Kay and her minions. But somehow Eleven isn't among the detainees.

Instead, she's suddenly standing at the gate to the Upside Down, which is about to be destroyed forever by a bomb Hopper and Murray (Brett Gelman) set.

After a quick psychic conference with Mike, and a goodbye kiss set to "Purple Rain" by Prince, El is blown up with the Upside Down, and the gate to a wormhole and other worlds is closed for good. The show flashes forward 18 months to Hawkins, Indiana, being rebuilt as an idyllic version of Small Town America.

Everybody is mostly happy and attempting to move on − except for Mike. As he continues to grapple with his grief and almost skips out on his high school graduation, Hopper has a heart to heart with him and convinces him to show up. At the end of the ceremony, Mike notices something in the feedback of the speakers at graduation that reminds him of the same noise used against El by the government bad guys.

Mike's theory about Eleven in 'Stranger Things' series finale

Later in the day, while playing a final game of Dungeons & Dragons with Lucas, Will, Dustin and Max, Mike spins a story where El escaped and faked her death, with the help of Kali, whose superpowers involve illusions.

In his story, El is somewhere far away and safe, with three waterfalls. The scene flashes to an image of El, now with long hair and normal clothes, hiking up a stony mountain to a beautiful ridge overlooking waterfalls.

Mike and the rest of the crew don't know for certain if she's alive somewhere, and the show doesn't make it clear. There are a few things in favor of his theory. At the moment when El magically escaped the grip of the military, they were blasting the sort of kryptonite sound that causes her immense pain and blocks her ability to use her powers.

The El we saw standing in the gate to the Upside Down showed no evidence of (physical) pain. She seemed to disappear from the truck carrying everyone with remarkable speed. And her "sister" Kali seemed to show up in the season out of nowhere, after appearing before only in one widely-hated episode all the way back in Season 2. It's possible Kali was just a plot device to make Eleven's fate all the more ambiguous.

But whether or not she really survived can never be answered by what was shown on screen. Like Mike and his friends, fans will have to choose to believe it or not.

After all, stranger things have happened.